Question
Coxsackie viruses.
Answer
Coxsackieviruses are members of the Enterovirus genus (family Picornaviridae), small, non-enveloped, single-stranded positive-sense RNA viruses transmitted primarily by the faecal-oral route (and, to a lesser extent, respiratory droplets), causing a wide spectrum of clinical disease depending on the specific serotype and target tissue infected.
Classification: divided into Group A and Group B coxsackieviruses, historically distinguished by their differing pathological effects in suckling mice (Group A causes diffuse flaccid myositis; Group B causes focal necrotic lesions in multiple organs — brain, heart, pancreas, fat).
Clinical associations:
- Group A: hand, foot, and mouth disease (vesicular lesions on hands, feet, and oral mucosa, particularly in young children — most classically caused by Coxsackievirus A16, though enterovirus 71 also causes this syndrome and is associated with more severe neurological disease); herpangina (painful vesicular/ulcerative lesions on the soft palate/tonsillar pillars, with fever, in young children).
- Group B: myocarditis and pericarditis — Coxsackie B viruses are a leading viral cause; pleurodynia (Bornholm disease) — sudden-onset severe chest/abdominal pain from pleural/intercostal muscle inflammation; aseptic (viral) meningitis — coxsackieviruses (both groups) are a common cause of enteroviral aseptic meningitis; neonatal sepsis-like severe disseminated infection in newborns.
Laboratory diagnosis: viral culture (cytopathic effect in cell culture) from throat swab, stool, vesicle fluid, or CSF; RT-PCR — increasingly the preferred method, more rapid and sensitive; serology (rise in neutralizing antibody titre) less commonly used given multiple serotypes.
Treatment: primarily supportive, as no specific antiviral therapy is routinely available for most coxsackievirus infections; most illnesses are self-limiting, though myocarditis and severe neonatal disease can be serious.