Infectious Disease and Microbiology – Coxsackievirus Group

Overview

Coxsackieviruses are members of the enterovirus group and are divided mainly into coxsackievirus A and coxsackievirus B, each of which contains multiple serotypes.

They are common worldwide pathogens and are responsible for a wide range of clinical syndromes, including mucocutaneous disease, respiratory illness, myocarditis, meningitis, and neonatal disseminated infection.

Microbiologic Characteristics

Coxsackieviruses are:

• Single-stranded, positive-sense RNA viruses

• Nonenveloped (naked)

• Viruses with icosahedral symmetry

Because they are nonenveloped, they are relatively resistant to environmental conditions compared with enveloped viruses.

Epidemiology

Coxsackievirus infections occur worldwide and are a common cause of human illness.

Transmission is mainly through the fecal–oral route, although respiratory spread can also occur, particularly in syndromes involving the upper respiratory tract.

Children are commonly affected, but infection can occur at any age.

Hand-Foot-and-Mouth Disease

Coxsackievirus A is classically associated with hand-foot-and-mouth disease.

This syndrome is characterized by:

• Oral vesicles or ulcers

• Vesicular or papular lesions on the hands

• Lesions on the feet

• Fever

• Malaise

The mucosal lesions represent an enanthem, while the skin lesions represent an exanthem.

Herpangina

Herpangina is another classic coxsackievirus-associated syndrome.

It usually presents with:

• Fever

• Sore throat

• Painful vesicles or ulcers in the posterior oropharynx

• Difficulty swallowing

Coxsackievirus A is an important cause.

Upper Respiratory Tract Infection

Coxsackieviruses may produce nonspecific upper respiratory tract infections characterized by symptoms such as:

• Sore throat

• Rhinorrhea

• Cough

• Fever

• Malaise

Pleurodynia

Coxsackievirus B is classically associated with epidemic pleurodynia, also called Bornholm disease.

Patients may develop sudden episodes of:

• Severe chest pain

• Upper abdominal pain

• Fever

• Pain worsened by respiration or movement

The pain is related to inflammation of the chest wall and intercostal muscles.

Myopericarditis

Coxsackievirus B is an important viral cause of myocarditis and pericarditis.

Clinical manifestations may include:

• Chest pain

• Dyspnea

• Palpitations

• Arrhythmias

• Signs of heart failure

• Pericarditic pain

Severe myocarditis can occasionally result in substantial cardiac dysfunction.

Acute Hemorrhagic Conjunctivitis

Certain enteroviruses, including some coxsackievirus strains, may cause acute hemorrhagic conjunctivitis.

Patients may develop:

• Red eyes

• Eye discomfort

• Photophobia

• Conjunctival hemorrhage

• Excessive tearing

Central Nervous System Infection

Coxsackieviruses are important causes of aseptic meningitis.

They may also cause:

• Encephalitis

• Meningoencephalitis

• Rare paralytic syndromes

Neurologic infection may occur in both children and adults.

Chronic Meningoencephalitis

A particularly important complication can occur in severely immunocompromised patients, especially those with agammaglobulinemia.

These patients may develop chronic enteroviral meningoencephalitis because they lack adequate antibody-mediated immunity to control the infection.

Neonatal Disseminated Infection

Newborns can develop severe disseminated coxsackievirus infection.

This may involve multiple organs and can produce:

• Sepsis-like illness

• Myocarditis

• Hepatitis

• Meningoencephalitis

• Coagulopathy

• Shock

Neonatal disease may be rapidly progressive and life-threatening.

Diagnosis

Diagnosis can be established using:

• PCR

• Virologic culture

• Serologic testing

PCR is particularly useful for detecting enteroviral RNA in appropriate clinical specimens, including cerebrospinal fluid in suspected meningitis.

Treatment

Treatment is primarily supportive and symptomatic.

Management depends on the clinical syndrome and may include:

• Hydration

• Antipyretics and analgesics

• Cardiac monitoring for myocarditis

• Respiratory support when necessary

• Intensive supportive care in severe neonatal infection

Specific Antiviral Therapy

There is no routinely available specific antiviral treatment for most coxsackievirus infections.

Most uncomplicated infections resolve spontaneously.

Prevention

Prevention is based primarily on reducing transmission.

Important measures include:

• Careful hand hygiene

• Proper disposal of fecal material

• Avoiding close contact with infected secretions

• Enteric precautions during the contagious period

• Respiratory precautions when appropriate, such as during herpangina

Older recommendations include enteric isolation for approximately 1 week.

High-Yield Clinical Associations

Coxsackievirus A

→ Hand-foot-and-mouth disease

→ Herpangina

Coxsackievirus B

→ Pleurodynia

→ Myocarditis

→ Pericarditis

Both groups

→ Aseptic meningitis and other enteroviral syndromes

Exam Essentials

Group: Enterovirus

Genome: Positive-sense single-stranded RNA

Envelope: None

Capsid: Icosahedral

Distribution: Worldwide

Major syndromes: Hand-foot-and-mouth disease, herpangina, pleurodynia, myopericarditis, meningitis

Severe neonatal disease: Disseminated infection

High-risk chronic CNS disease: Agammaglobulinemia

Diagnosis: PCR, culture, serology

Treatment: Supportive

Specific antiviral: None routinely available

Prevention: Enteric and respiratory hygiene precautions

Key clinical pearl: The classic exam distinction is coxsackie A → hand-foot-and-mouth disease and herpangina, whereas coxsackie B → pleurodynia and myopericarditis.