Differentials
Common
Nonhemorrhagic volume losses
History
often older adults; may be a history of vomiting and diarrhea, prolonged period of illness, or diuretic use; burns; profound sweating; decreased oral intake; bronchorrhea or draining pleural effusion; history of or risk factors for diabetes insipidus; risk factors for diabetic ketoacidosis or hyperosmolar hyperglycemic state; may be fever; thirst; fatigue; dizziness on standing
Exam
hypotension may be profound if there is shock with decreasing level of consciousness; fever; tachycardia; weak pulse; dry mucous membranes; decreased skin turgor
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
elevated BUN and creatinine; normal, elevated or low serum sodium; low serum potassium (with diarrhea); elevated hematocrit; elevated WBC count (if infectious cause)
More - ECG:
sinus tachycardia, tachyarrhythmia
- urinalysis:
high specific gravity
Other investigations
- ABG:
prolonged diarrhea: low bicarbonate; prolonged vomiting: high bicarbonate
More - random urine sodium:
<20 mmol/L (<20 mEq/L)
More - fractional excretion of sodium:
<1%
More - random urine creatinine:
elevated
More - random urine osmolality:
>450 mmol/kg (>450 mOsm/kg)
- stool culture:
normal; may show growth of bacteria, toxins or parasites
More - urine microscopy and culture:
normal or evidence of bacterial growth
More
Upper gastrointestinal bleed
History
history of nonsteroidal anti-inflammatory drugs use, often with concomitant corticosteroid use; may be history of peptic ulcer disease or chronic liver disease; upper abdominal pain (frequently absent in older adults); hematemesis; coffee ground emesis; fatigue, dizziness
Exam
hypotension may be profound if there is shock with decreasing level of consciousness; pallor, abdominal tenderness (usually upper abdomen); signs of chronic liver disease (e.g., palmar erythema, spider angiomata, petechiae, jaundice, hepatomegaly, ascites, muscle wasting, gynecomastia, pedal and ankle edema); rectal exam positive for melena
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile, type and cross):
normal or low Hb, elevated BUN:creatinine ratio; may be abnormal prothrombin time and prolonged INR
- ECG:
sinus tachycardia
- upper gastrointestinal endoscopy:
source of bleeding may be visualized
More
Other investigations
Lower gastrointestinal bleed
History
may be known history of inflammatory bowel disease or lower gastrointestinal tumor; melena; hematochezia; abdominal pain (left-sided in older adult suggests diverticular disease); fatigue; dizziness
Exam
hypotension may be profound if there is hemorrhagic shock with decreasing level of consciousness; may be blood on digital rectal exam; abdominal exam may be normal, or may be tenderness; patients with colonic tumor may have a palpable abdominal mass
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile, type and cross):
normal or low Hb; elevated BUN:creatinine ratio; may be abnormal prothrombin time and prolonged INR
- ECG:
sinus tachycardia
- colonoscopy:
source of bleeding may be visualized (e.g., diverticulae, colonic angioma, polyps, evidence of inflammatory bowel disease or colonic tumor)
- mesenteric angiography:
the site of active bleeding may be seen[88]
Other investigations
Dialysis-induced hypotension
History
presence of hypotension during dialysis session; previous history of dialysis-induced hypotension; presence of other condition that may predispose to hypotension (e.g., intercurrent infective illness leading to dehydration); diabetes, large interdialytic weight gain, female sex and low body weight are risk factors for dialysis-induced hypotension
Exam
tachycardia; weak pulse; increased skin turgor; dry mucous membranes; signs of chronic renal failure (e.g., increased skin pigmentation)
1st investigation
- clinical exam:
usually a clinical diagnosis
- ECG:
may be sinus tachycardia, evidence of tachyarrhythmia
Other investigations
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
elevated BUN and creatinine; low or high serum sodium; elevated hematocrit
Trauma
History
history of road traffic accident, fall, penetrating injury, blunt trauma
Exam
may be signs of external bleeding; open fracture; tender abdomen concealing intra-abdominal hemorrhage; decreased breath sounds and dullness to percussion on chest examination may indicate hemothorax; unstable pelvis if fractured; narrow pulse pressure
1st investigation
- CBC, type and cross:
may be low or normal Hb
- coagulation screen:
serum PT, INR and PTT may be prolonged or elevated
- x-ray trauma series:
hemothorax if chest injury, widened mediastinum suggests aortic disruption, pelvic fractures if present
More - Focused Assessment with Sonography for Trauma scan:
positive if free fluid in the abdomen or pericardium is identified
More - CT scan:
may show blood in abdominal cavity
More
Other investigations
- diagnostic peritoneal lavage:
blood in the abdomen on drainage of fluid suggests intra-abdominal bleed
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Acute coronary syndrome
History
history of risk factors for coronary artery disease (CAD) (e.g., smoking, hyperlipidemia, diabetes, family history of CAD); chest pain (often described as heavy or tight) radiating to arms, back, neck, or jaw; chest pain may be absent in older adults and people with diabetes; dyspnea; nausea; diaphoresis
Exam
hypotension may be profound if there is cardiogenic shock + decreasing level of consciousness; diaphoretic appearance; pallor; tachycardia; bradycardia; new abnormal pulse rhythm; distended jugular veins; other signs of heart failure (e.g., dyspnea, crackles at lung bases); new heart murmur
1st investigation
- ECG:
ST segment elevation or depression, or T wave changes
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, serum troponin, d-dimer, coagulation profile):
elevated serum troponin
- coronary angiogram:
presence of thrombus with occlusion of the artery
- chest x-ray:
evidence of pulmonary congestion/pleural effusion if secondary heart failure, may show enlarged cardiac shadow
Acute heart failure
History
acute onset shortness of breath; orthopnea; may be history of known heart failure or of risk factors (e.g., recent myocardial infarction, valvular heart disease, hypertrophic cardiomyopathy, known bacterial endocarditis, rheumatic fever, or Marfan syndrome)
Exam
hypotension may be profound if there is cardiogenic shock plus decreasing level of consciousness; distended jugular veins; crackles at lung bases; new murmur; additional heart sounds; fever in endocarditis; mitral facies (mild cyanosis of lips/cheeks without clubbing) may be present if mitral stenosis is a causative factor; may be signs of Marfan syndrome (e.g., tall stature, wide arm span, high arched palate, arachnodactyly with positive thumb sign)
1st investigation
- ECG:
nearly always abnormal; may show arrhythmias, ischemic ST and T wave changes
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, serum troponin, d-dimer, coagulation profile):
serum troponin: elevated in acute coronary ischemia; low Hb if anemia the cause; WBC count may be elevated
- serum thyroid-stimulating hormone and free T4:
abnormal if associated hypo- or hyperthyroidism
- chest x-ray:
cardiomegaly, pulmonary congestion, pleural effusion, valvular or pericardial calcification
- echocardiogram:
new valvular dysfunction (e.g., mitral regurgitation); endocarditis: may show vegetations
Other investigations
- B-type natriuretic peptide (BNP):
>400 picogram/mL may be indicative of heart failure
More - fasting serum lipids (total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides):
variable
- blood cultures:
endocarditis: positive cultures
Dysrhythmia
History
more common in older patients; symptoms may be acute, chronic, or paroxysmal; palpitations; chest pain; syncope; dizziness; dyspnea; may be history of dysrhythmia, heart disease or heart failure
Exam
signs may be acute, chronic or paroxysmal; hypotension may be profound if there is cardiogenic shock + decreasing level of consciousness; tachycardia; bradycardia; irregular pulse; may have signs of heart failure (e.g., distended jugular veins, crackles at lung base, peripheral edema)
1st investigation
- ECG:
dysrhythmia demonstrated
More - basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, serum troponin, d-dimer, coagulation profile):
may be low Hb, abnormal serum electrolytes
- serum thyroid-stimulating hormone, free T4:
thyroid-stimulating hormone and free T4 may be abnormal if hypo- or hyperthyroidism cause of dysrhythmia
Other investigations
- cardiac telemetry:
dysrhythmia demonstrated
- 24-hour ECG monitor:
dysrhythmia demonstrated
Acute pulmonary embolism
History
dyspnea; pleuritic chest pain (often absent in older adults); hemoptysis; palpitations; feeling of apprehension; may be history of recent immobilization (e.g., prolonged air flight, surgery), obesity, pregnancy/postpartum period, inherited thrombophilias, active malignancy, recent trauma/fracture, or history of deep vein thrombosis
Exam
hypotension may be profound if large pulmonary embolism (PE) but in other cases physical exam can be normal; may be tachypnea; pleural rub on chest auscultation; tachycardia; low oxygen saturations on pulse oximetry (may be transient); calf tenderness
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, serum troponin, d-dimer, coagulation profile):
d-dimer: normal or elevated
More - ABG:
may be normal; hypoxia and hypocapnia suggestive of PE
- ECG:
tachycardia, new right axis deviation, new right bundle branch block, S wave in lead I, Q wave with T-wave inversion in lead III
More - chest x-ray:
band atelectasis, elevation of hemidiaphragm, prominent central pulmonary artery, oligemia at site of embolism
More
Other investigations
- multi-detector computed tomography pulmonary angiography:
direct visualization of thrombus in a pulmonary artery, appears as a partial or complete intraluminal filling defect
More - ventilation/perfusion (V/Q) scan:
normal, low, intermediate, and high probability; PE likely when an area of ventilation is not perfused
More - transthoracic echocardiography:
may show features indicating right ventricular strain/dysfunction
- pulmonary angiography:
demonstrates complete or incomplete filling defect in the pulmonary artery
More - duplex ultrasound of femoral and calf veins:
noncompressible leg veins
More - serum thyroid-stimulating hormone, free T4 (older adults only):
normal
Vasovagal syncope
History
previous history (including childhood) of faints; typical premonitory warning symptoms of feeling warm, nauseated, dizzy, distant from surroundings (may not be reported by older patients)
Exam
normal cardiac examination; features of witnessed event include transient loss of consciousness, may be myoclonic type jerks during the event, may appear flushed initially with pallor immediately preceding loss of consciousness
1st investigation
- clinical exam:
diagnosis may be made on history and exam findings alone
More - ECG:
normal
Other investigations
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
normal
- serum thyroid-stimulating hormone, free T4 and serum vitamin B12 (older adults only):
normal
- tilt table testing with beat-to-beat (phasic) BP monitoring (e.g., digital artery photoplethysmography):
reproduction of symptoms with prolonged (40 min) tilt
More
Medication-related
History
history of recently introduced medication known to produce hypotension; common responsible drug classes include beta-blockers, alpha-blockers, diuretics, nitrates, calcium channel blockers, ACE inhibitors, L-dopa, tricyclic antidepressants, phenothiazines, opioids (in high doses), intravenous acetaminophen in critically ill hospitalized patients; more common in older adults
Exam
change in BP readings date from after introduction of new medication, and improvement noted after discontinuation of drug; no specific physical exam findings to suggest other cause
1st investigation
- discontinuation of suspected precipitating medication:
clinical improvement on discontinuation of medication
More - urine toxicology screen:
may be positive for opioids
Other investigations
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
normal
- serum thyroid-stimulating hormone and free T4 and serum vitamin B12 (older adults only):
normal
- ECG:
normal
Pregnancy (uncomplicated)
History
woman of childbearing age; delayed menstruation; history of unprotected sexual intercourse; may be known pregnancy or history may indicate the patient is unaware she is pregnant
Exam
gravid uterus on abdominal or pelvic exam; fetal heart on auscultation
1st investigation
- urinary pregnancy test:
positive
- serum beta HCG:
positive
Other investigations
- pelvic ultrasound:
live fetus present
Sepsis
History
symptoms of localized infection, nonspecific symptoms include fever or shivering, dizziness, nausea and vomiting, muscle pain, feeling confused or disoriented; may be history of risk factors (e.g., immunosuppression, pregnancy or postpartum period, frailty, recent surgery or invasive procedures, intravenous drug use, or breach of skin integrity)
Exam
tachycardia, tachypnea, hypotension, fever >101°F (>38°C) or hypothermia >97°F (<36°C), prolonged capillary refill, mottled or ashen skin, cyanosis, low oxygen saturation, newly altered mental state, reduced urine output
1st investigation
- blood culture:
may be positive for organism
More - serum lactate:
may be elevated; levels >18 mg/dL (>2 mmol/L) associated with adverse prognosis; even worse prognosis with levels ≥36 mg/dL (≥4 mmol/L) elevated
More - CBC with differential:
WBC count >12×10⁹/L (12,000/mL) (leukocytosis); WBC count <4×10⁹/L (4000/mL) (leukopenia); or a normal WBC count with >10% immature forms; low platelets
More - C-reactive protein:
elevated
- blood urea and serum electrolytes:
serum electrolytes may be deranged; blood urea may be elevated
- serum creatinine:
may be elevated
More - LFTs:
may show elevated bilirubin, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and gamma glutamyl transpeptidase
More - coagulation studies:
may be abnormal
- ECG:
may show evidence of ischemia, atrial fibrillation, or other arrhythmia; may be normal
More - ABG:
may be hypoxia, hypercapnia, elevated anion gap, metabolic acidosis
Other investigations
- urine microscopy and culture:
may be positive for nitrites, protein or blood; elevated leukocyte count; positive culture for organism
- sputum culture:
may be positive for organism
- chest x-ray:
may show pleural effusion, consolidation, cardiac abnormalities or a pneumothorax, demonstrates position of central venous catheter and tracheal tube
- echocardiogram:
inadequate left ventricular filling suggests hypovolemia; vegetations if endocarditis cause of sepsis
More - lumbar puncture:
may be elevated WBC count, presence of organism on microscopy and positive culture
More
Chronic liver disease
History
known history of chronic liver disease; pruritus; abdominal swelling; confusion; lethargy; weight loss; weakness; bruising; may be worsening light-headedness and unsteadiness in presence of concurrent hematemesis, melena or other symptoms of gastrointestinal bleed; history of sepsis (fever, anorexia, focal symptoms depending on site of infection)
Exam
may be jaundice; muscle wasting; gynecomastia; palmar erythema; spider angiomata; petechiae; ascites; distended abdominal veins; hepatosplenomegaly; signs of encephalopathy (e.g., memory, attention, and concentration deficits, confusion, asterixis, nystagmus, clonus, rigidity, coma)
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
elevated liver enzymes; elevated bilirubin (conjugated); may be low Hb and low platelets; INR may be elevated
- serum thyroid-stimulating hormone, free T4 (older adults only):
normal
- ECG:
normal
Other investigations
- blood cultures:
concurrent sepsis: infective organism isolated
- urine microscopy and culture:
concurrent urinary infection: infective organism isolated
- paracentesis:
concurrent infective peritonitis: infective organism isolated
More - upper gastrointestinal endoscopy:
may demonstrate source of gastrointestinal bleed, varices may be visualized
Parkinson disease
History
more common in older adults; usually long-standing history of Parkinson disease; may be recent initiation or change in anti-Parkinsonian medication, or symptoms of concurrent general medical illness (e.g., dysuria and urinary frequency with urosepsis, or cough with purulent sputum with pneumonia)
Exam
bradykinesia; tremor; increased tone; postural instability; stooped shuffling gait with reduced arm-swing, mask-like face; signs of intercurrent infection (e.g., fever, crackles on chest auscultation)
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
CBC may show elevated WBC count if infection present
- serum thyroid-stimulating hormone, free T4 and serum B12 (older adults only):
normal
- ECG:
normal
Other investigations
Uncommon
Ruptured abdominal aortic aneurysm
History
abdominal pain radiating to back; abdominal distension; bilateral flank pain; light-headedness; may be a history of risk factors (e.g., smoking, peripheral vascular disease, known history of aneurysm)
Exam
hypotension may be profound with decreasing level of consciousness; abdominal tenderness; pulsatile mass; weak peripheral pulses
1st investigation
- clinical exam:
diagnosis of acute rupture is usually made by history and clinical findings
More
Other investigations
- bedside abdominal ultrasound:
may demonstrate site of leak or extravasation; color flow Doppler can aid detection; sensitivity and specificity for rupture are low
More - CT thorax and abdomen:
impending rupture: may demonstrate blood within the thrombus (crescent sign), low thrombus-to-lumen ratio, retroperitoneal hematoma, discontinuity of the aortic wall, or extravasation of contrast into the peritoneal cavity
More
Ectopic pregnancy
History
women of childbearing age; amenorrhea; may be known pregnancy; abdominal pain; vaginal bleeding; may be history of previous ectopic pregnancy, prior tubal surgery, pelvic inflammatory disease, or intrauterine contraception use
Exam
tachycardia; abdominal tenderness and guarding; decreased bowel sounds; cervical motion tenderness; vaginal bleeding
Other investigations
- transvaginal ultrasound:
visualization of ectopic pregnancy; empty uterus
Retroperitoneal bleed
History
symptoms may be vague; groin, lower abdominal, or back pain; history of risk factors (e.g., recent anticoagulation use, recent history of cardiac or femoral angiography, recent obstetric procedure in women of childbearing age)
Exam
unexplained tachycardia; tenderness in lower abdomen on side of bleed; may be bruising of flank; diaphoresis if severe; profound hypotension with decreasing levels of consciousness if shock present
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs coagulation profile, type and cross):
low Hb; INR may be elevated
- ECG:
normal, or tachycardia
Other investigations
- CT abdomen:
hematoma may be visualized
- CT angiogram:
may demonstrate active bleeding site if bleeding is ongoing
Severe acute pancreatitis
History
Sudden-onset continuous upper abdominal pain, typically radiating to the back; nausea and vomiting, malaise; history of alcohol use or gallstones, may be history of azathioprine, mercaptopurine or didanosine use
Exam
Epigastric or left upper quadrant tenderness with voluntary guarding, abdominal distension, may be reduced bowel sounds; hypotension, dry mucous membranes, reduced skin turgor, oliguria, sweating, tachycardia, tachypnea; signs of pleural effusion (more commonly left side); jaundice
1st investigation
- serum lipase or amylase:
>3 times the upper limit of normal
More - basic test panel (CBC, serum electrolytes, serum calcium, blood glucose, serum LFTs):
CBC: leukocytosis, elevated hematocrit indicates dehydration; elevated urea and/or creatinine in dehydration; elevated aminotransferases suggests gallstones as the cause; hypercalcemia is a rare cause of pancreatitis
- C-reactive protein:
elevated
- arterial blood gas:
may show hypoxemia or acid-base disturbance
Other investigations
- chest x-ray:
may show atelectasis and pleural effusion
- transabdominal ultrasound:
may show gallstones; may show pancreatic inflammation, peripancreatic stranding, calcifications or fluid collections
More
Carotid sinus syndrome (cardioinhibitory subtype)
History
history of recurrent or unexplained falls, drop attacks or collapse episodes occurring in an older adult (usually >70 years); patient may not report classical precipitant of neck extension or turning
Exam
usually unremarkable clinical findings; on clinical exam there are no differentiating features from the vasodepressor subtype of carotid sinus syndrome and differential findings are almost always at time of tilt table testing with carotid sinus massage
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, serum troponin, d-dimer, coagulation profile):
normal
- serum thyroid-stimulating hormone, free T4 and serum vitamin B12 (older adults only):
normal
- ECG:
usually normal; may show first degree heart block
- tilt table test with carotid sinus massage:
inducible cardiac pause/asystole exceeding 3 seconds
Other investigations
Severe hypothyroidism
History
weight gain; weakness; lethargy; slow speech; cold sensation; forgetfulness; constipation; neck swelling
Exam
evidence of severe hypothyroidism (e.g., coma, hypothermia, signs of heart failure); coarse hair; facial edema; bradycardia; eyelid edema; thick tongue
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, serum troponin, coagulation profile):
CBC: may have elevated MCV
- serum thyroid-stimulating hormone, free T4:
primary hypothyroidism: elevated thyroid-stimulating hormone, low T4
- serum B12 (older adults only):
normal
Other investigations
Tension pneumothorax
History
sudden onset pleuritic chest pain; severe and worsening dyspnea; rapid deterioration; may be risk factors (e.g., recent placement of central venous pressure line, history of emphysema or chest trauma)
Exam
acute distress; cyanosis; profuse diaphoresis; tachycardia; absent unilateral breath sounds; hyperresonance to percussion on affected side; tracheal shift from midline; hypotension develops rapidly with subsequent loss of consciousness
1st investigation
- diagnostic and therapeutic needle thoracostomy:
hiss of air as catheter/needle enters the pleural space
More
Other investigations
- post-decompression chest x-ray:
shows a visceral pleural line; confirms position of intercostal drain
More
Cardiac tamponade
History
chest pain reduced by sitting forward; shortness of breath; may be risk factors present (e.g., recent myocardial infarction, pericarditis, coronary angiogram, or cardiac surgery)
Exam
hypotension may be profound with decreasing level of consciousness; increased respiratory rate; distended jugular veins, reduced heart sounds and hypotension (Beck triad); tachycardia; pulsus paradoxus (high positive predictive value and sensitivity, though lower specificity)
1st investigation
- chest x-ray:
enlargement of cardiac shadow
- ECG:
rhythm strip: beat-to-beat electrical alternans
- echocardiogram:
typically: large pericardial effusion (>20 mm of echo-free space in diastole between the visceral and parietal pericardium); chamber collapse and respiratory variation of ventricular filling
More
Other investigations
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, serum troponin, d-dimer, coagulation profile):
may be low Hb if anemia is a related cause; viral pericarditis: elevated WBC count; elevated troponin if cardiac trauma or myocardial infarction
- erythrocyte sedimentation rate:
elevated in the presence of inflammatory or infective cause
Situational syncope
History
previous history of faints precipitated by similar event, recognized precipitants include micturition, defecation, exercise, brass instrument playing, weightlifting, and eye exam
Exam
normal cardiac exam; features of witnessed event include transient loss of consciousness, may be myoclonic type jerks during the event, pallor
1st investigation
- clinical exam:
diagnosis may be made on history and exam findings alone
More - ECG:
normal
Other investigations
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
normal
- serum thyroid-stimulating hormone, free T4 and serum vitamin B12 (older adults only):
normal
Anaphylaxis
History
history of recent ingestion/exposure to known allergen (e.g., bee sting); acute onset of symptoms with rapid deterioration; wheeze; rash; swollen lips or tongue; swollen eyelids; pruritus; agitation; anxiety; impending sense of doom (angor animi); nausea; vomiting; diarrhea; light-headedness
Exam
rapidly progressive signs; signs of bronchospasm (e.g., audible wheeze, use of accessory muscles); erythematous confluent rash or itchy urticarial wheals; angioedema of tongue, lips or eyelids; flushing; rhinitis; inspiratory stridor; syncope; delirium; coma
1st investigation
- clinical exam:
diagnosis usually made clinically with treatment started without delay for testing
More
Other investigations
- mast cell tryptase:
may be elevated; can range from insignificantly elevated to levels above 100 nanograms/mL
More - post-episode CBC:
eosinophilia
- post-episode serum histamine:
>1.1 micrograms/L
- post-episode radioallergosorbent test:
>0.35 international units/L
- post-episode specific skin tests (Ig E):
>3mm diameter and greater than control
- post-episode challenge test:
objective symptoms of allergy response
- post-episode urine test for N-methyl histamine:
increased compared with baseline
Carotid sinus syndrome (vasodepressor subtype)
History
history of recurrent or unexplained falls, drop attacks or collapse episodes occurring in an older adult (usually >70 years); patient may not report classical precipitant of neck extension or turning
Exam
usually unremarkable clinical findings; typically there are no definite differentiating features on clinical exam from the cardio-inhibitory subtype of carotid sinus syndrome and tilt table test with carotid sinus massage is required
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, serum troponin, d-dimer, coagulation profile):
normal
- serum thyroid-stimulating hormone, free T4 and serum vitamin B12 (older adults only):
normal
- ECG:
normal
- tilt table test with carotid sinus massage:
symptomatic fall in BP ± syncope precipitated. Pure vasodepressor subtype does not have an associated cardiac pause
More
Other investigations
Diabetic autonomic neuropathy
History
known history of diabetes mellitus; may be known peripheral neuropathy; loss of sensation in feet and hands; painless injuries; dysesthesia
Exam
impaired peripheral (glove and stocking distribution) sensation; evidence of painless injuries particularly of feet; absent ankle reflexes; orthostatic hypotension
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
random blood glucose: may be normal if diabetes is well controlled, or elevated if poorly controlled/new diagnosis
More - serum thyroid-stimulating hormone, free T4 and serum vitamin B12 (older adults only):
normal
- ECG:
may be normal; comorbid coronary disease: may demonstrate ischemic changes
- fasting blood glucose:
new diagnosis of diabetes: 126 mg/dL or higher
More - HbA1c:
variable depending on degree of glucose control
More
Other investigations
- nerve conduction studies:
reduction in sensory nerve conduction velocity and a decrease in amplitude is the most sensitive and earliest result
More
Multi-system atrophy
History
more commonly older adult; parkinsonism symptoms recently noted; may be history of falls or unexplained injuries
Exam
bradykinesia; tremor; increased tone; upward gaze palsy; commonly orthostatic hypotension detected; parkinsonism, cerebellar, autonomic and urological dysfunction in any combination
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
CBC may show elevated WBC count if infection present
- serum thyroid-stimulating hormone, free T4 and serum vitamin B12 (older adults only):
normal
- ECG:
normal
Other investigations
Post-stroke
History
recent stroke, typically in preceding days; most commonly right cerebral hemisphere stroke; reduction in patient's level of consciousness or deterioration in his/her mobility and ability to sit upright over time; history of recent introduction of BP lowering medication
Exam
signs of stroke (neurological deficit dependent on cerebral region affected); BP measurements may appear normal at first glance but have shown a drop since initial admission (hypertensive) BP readings
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, serum troponin, d-dimer, coagulation profile):
normal
- serum thyroid-stimulating hormone, free T4 and serum vitamin B12 (older adults only):
normal
More
Other investigations
- ECG:
normal or ischemic changes
- fasting serum lipids ( total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides):
variable
Primary autonomic failure
History
may be a known history of autonomic failure and orthostatic hypotension; dizziness on standing; may be erectile dysfunction, constipation, decreased sweating; history of regular (daily) symptoms occurring within a short period (minutes) after posture change
Exam
no specific physical findings other than orthostatic hypotension; posture test positive (systolic BP falls >20 mmHg and diastolic BP falls >10 mmHg within 3 minutes orthostatic stress with lack of an adequate compensatory heart rate increase [>20 bpm]); if posture test normal should not deter from further investigation in the presence of suggestive history
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
normal
- serum thyroid-stimulating hormone, free T4 and serum vitamin B12 (older adults only):
normal
- ECG:
normal
Other investigations
- tilt table test with beat to beat BP monitoring (e.g., digital artery photoplethysmography):
profound and often prolonged hypotension in response to head up tilt often present; fall in systolic BP of >20 mmHg or diastolic BP >10 mmHg; supine hypertension may also be present; presence of presyncopal symptoms associated with hemodynamic changes
- specialized physiological tests (plasma norepinephrine; deep breathing: Valsalva maneuver test; electrophysiological tests; quantitative sudomotor axon reflex test [QSART]: heart rate variability test):
failure to release norepinephrine on standing; diminished beat-to-beat variation on ECG during inspiration and expiration; failure of the BP overshoot after release of the strain during Valsalva maneuver; reduction in sensory nerve conduction velocity and muscle denervation on electrophysiological tests; absence of sweat production on QSART; decreased heart rate variability
Amyloidosis
History
history of unexplained weight loss; parasthesia; shortness of breath; fatigue; dizziness on standing; may be a known history of amyloidosis, or of a chronic inflammatory condition known to predispose to amyloidosis development (e.g., rheumatoid arthritis)
Exam
macroglossia (specific for amyloidosis); periorbital purpura; lower limb edema which is resistant to diuretic therapy; elevated jugular venous pressure; orthostatic hypotension; signs of a chronic inflammatory condition (e.g., rheumatoid deformities of joints, erythematous, tender joints, rheumatoid nodules, skin lesions)
1st investigation
- serum and urine immunofixation:
clonal plasma cells demonstrated
- immunoglobulin free light chain assay:
abnormal kappa to lambda ratio
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
associated renal insufficiency or gastrointestinal bleed: may be low Hb; hepatic amyloid: elevated alk phos
- serum thyroid-stimulating hormone, free T4 and serum vitamin B12 (older adults only):
normal
- ECG:
may demonstrate conduction abnormalities
Other investigations
- tissue biopsy:
positive (green) birefringence with Congo Red stain
More
Adrenal suppression (iatrogenic)
History
More common in patients with chronic inflammatory disorders such as rheumatoid arthritis, polymyalgia rheumatica, or inflammatory bowel disease. May be associated with intercurrent illness or abrupt withdrawal of chronic steroids
Exam
Hypotension may be mild; lethargy and decreased level of consciousness; stigmata indicative of underlying chronic inflammatory disorder such as rheumatoid hands; cushingoid appearance
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
serum electrolytes: may be hyponatremia and hyperkalemia, serum BUN may be elevated; CBC: WBC count may be elevated with intercurrent illness
- serum thyroid-stimulating hormone, free T4 and serum vitamin B12 (older adults only):
normal
More - ECG:
normal
- morning serum cortisol:
<3 micrograms/dL
Other investigations
- adrenocorticotrophic hormone stimulation test:
low serum cortisol pre-administration of cosyntropin with failure to rise after administration (<18 micrograms/dL)
Addison disease
History
weight loss; anorexia; increased pigmentation; fatigue; nausea and vomiting; salt craving; dizziness
Exam
hyperpigmentation (commonly mucous membranes and sun-exposed areas, more pronounced in palmar creases, areas of friction, and scars)
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
serum electrolytes: may be hyponatremia and hyperkalemia, serum BUN may be elevated; CBC: may be low Hb, eosinophilia
- serum thyroid-stimulating hormone, free T4 and serum vitamin B12 (older adults only):
normal
More - ECG:
normal
- morning serum cortisol:
<3 micrograms/dL
More
Other investigations
- adrenocorticotropic hormone stimulation test:
low serum cortisol pre-administration of cosyntropin with failure to rise after administration (<18 micrograms/dL)
Hypopituitarism
History
failure to thrive in childhood; short stature; failure of secondary characteristics; oligomenorrhea; infertility; headache; visual field defects; blurred vision
Exam
dry skin; breast atrophy; increased body mass index; loss of axillary and pubic hair; ophthalmoplegia
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
low serum sodium
- serum thyroid-stimulating hormone, free T4:
low free T4, low or normal thyroid-stimulating hormone
- morning serum cortisol:
<3 micrograms/dL
- morning serum testosterone, LH, FSH (in men):
all low
- morning serum estradiol, LH, FSH (in women):
all low
- serum prolactin:
may be elevated
Other investigations
- adrenocorticotrophic hormone stimulation test:
low serum cortisol pre-administration of cosyntropin with failure to rise after administration (<18 micrograms/dL)
- serum insulin like growth factor:
low
Thiamine deficiency
History
presence of suggestive risk factors (e.g., alcohol abuse, recurrent vomiting, chronic diarrhea, postgastrointestinal surgery, AIDS, total parenteral nutrition, diet of polished rice); fatigue; weakness; muscle aches; reduced peripheral sensation; swollen legs; poor balance; confusion; paresthesia
Exam
peripheral edema; reduced knee jerks and other tendon reflexes; severe muscle weakness; muscle wasting; tachycardia; signs of Wernicke encephalopathy (e.g., mental state changes such as acute confusion, ataxia, and ocular abnormalities such as nystagmus and strabismus)
1st investigation
- trial of thiamine replacement therapy:
clinical improvement may support diagnosis
- erythrocyte thiamine pyrophosphate level:
reduced
More - basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
CBC: macrocytosis
- serum thyroid-stimulating hormone, free T4:
normal
More - serum B12 (older adults only):
normal
- ECG:
normal
Other investigations
- ABG:
elevated anion gap, metabolic acidosis
- serum lactate:
elevated
- MRI brain:
Wernicke encephalopathy: bilateral increased T2 signal in the paraventricular regions of the thalamus, hypothalamus, mammillary bodies, periaqueductal region, fourth ventricle floor, and midline cerebellum
More
Vitamin B12 deficiency
History
may be known vitamin B12 deficiency; may be risk factors present (e.g., elderly people, patients with chronic malabsorption, history of gastric resection or bypass, and those taking certain medications such as metformin, proton pump inhibitors); lower limb numbness; other parasthesia; depressed mood
Exam
decreased vibration sense; gait abnormalities; decreased peripheral sensation; absent ankle jerks; signs of depression or dementia; exam may be normal; late signs: angular cheilitis, glossitis, pallor and bruising
1st investigation
- basic test panel (CBC, serum electrolytes, blood glucose, serum LFTs, coagulation profile):
CBC: may be normal but may be low Hb, elevated MCV, low hematocrit; peripheral blood smear: megalocytes, hypersegmented polymorphonucleated cells
- serum vitamin B12:
<200 picograms/mL is highly suggestive of deficiency
More - serum thyroid-stimulating hormone, free T4 (older adults only):
normal
More - ECG:
normal
- reticulocyte count:
low corrected reticulocyte index
Other investigations
Carcinoid syndrome
History
associated symptoms of flushing, diarrhea, abdominal pain, palpitations and wheeze
Exam
peripheral edema secondary to right heart failure, tachycardia, telangiectasia, cardiac murmur, hepatomegaly, wheeze, abdominal mass
1st investigation
- 24 hours of urinary excretion of 5-hydroxyindole acetic acid:
elevated
More - CT scan chest, abdomen and pelvis:
identifies location of primary tumor and presence of liver metastases
Other investigations
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