Gastroenteritis is generally self-limited.
Each syndrome related to listeriosis has its own prognosis and is determined by the immunologic status and concurrent health problems of the individual.[1]Mylonakis E, Hofmann EL, Calderwood SB. Central nervous system infection with Listeria monocytogenes. 33 years' experience at a general hospital and review of 776 episodes from the literature. Medicine (Baltimore). 1998 Sep;77(5):313-36.
http://www.ncbi.nlm.nih.gov/pubmed/9772921?tool=bestpractice.com
[31]Pinner RW, Schuchat A, Swaminathan B, et al. Role of foods in sporadic listeriosis. II. Microbiologic and epidemiologic investigation. The Listeria Study Group. JAMA. 1992 Apr 15;267(15):2046-50.
http://www.ncbi.nlm.nih.gov/pubmed/1552640?tool=bestpractice.com
[29]Schwartz B, Hexter D, Broome CV, et al. Investigation of an outbreak of listeriosis: new hypotheses for the etiology of epidemic Listeria monocytogenes infections. J Infect Dis. 1989 Apr;159(4):680-5.
http://www.ncbi.nlm.nih.gov/pubmed/2494267?tool=bestpractice.com
[21]Centers for Disease Control and Prevention. Listeria (Listeriosis): information for health professionals and laboratories. Mar 2021 [internet publication].
https://www.cdc.gov/listeria/technical.html
In one national observational cohort study, the strongest mortality predictors for both bacteraemia and neurolisteriosis were ongoing cancer, multi-organ failure, aggravation of any pre-existing organ dysfunction, and monocytopenia.[56]Charlier C, Perrodeau É, Leclercq A, et al; MONALISA study group. Clinical features and prognostic factors of listeriosis: the MONALISA national prospective cohort study. Lancet Infect Dis. 2017 May;17(5):510-9.
http://www.ncbi.nlm.nih.gov/pubmed/28139432?tool=bestpractice.com
Meningoencephalitis was the most prevalent CNS manifestation, occuring in 84% of patients. Brainstem involvement was reported in 17% of patients with CNS involvement.[56]Charlier C, Perrodeau É, Leclercq A, et al; MONALISA study group. Clinical features and prognostic factors of listeriosis: the MONALISA national prospective cohort study. Lancet Infect Dis. 2017 May;17(5):510-9.
http://www.ncbi.nlm.nih.gov/pubmed/28139432?tool=bestpractice.com
In the same study, only 5% of pregnant women experienced an uneventful outcome. Almost a quarter of women experienced fetal loss.[56]Charlier C, Perrodeau É, Leclercq A, et al; MONALISA study group. Clinical features and prognostic factors of listeriosis: the MONALISA national prospective cohort study. Lancet Infect Dis. 2017 May;17(5):510-9.
http://www.ncbi.nlm.nih.gov/pubmed/28139432?tool=bestpractice.com
Seventy-five percent of neonates born to mothers with listeriosis are complicated with clinical neonatal Listeria infection.[1]Mylonakis E, Hofmann EL, Calderwood SB. Central nervous system infection with Listeria monocytogenes. 33 years' experience at a general hospital and review of 776 episodes from the literature. Medicine (Baltimore). 1998 Sep;77(5):313-36.
http://www.ncbi.nlm.nih.gov/pubmed/9772921?tool=bestpractice.com
[2]Mylonakis E, Paliou M, Hofmann EL, et al. Listeriosis during pregnancy: a case series and review of 222 cases. Medicine (Baltimore). 2002 Jul;81(4):260-9.
http://www.ncbi.nlm.nih.gov/pubmed/12169881?tool=bestpractice.com