Introduction

This chapter will deal with cytomegalovirus (CMV) pulmonary disease in the immunocompromised host.

The expression of CMV disease is heavily dependent on the immune integrity of the host (Table 10.1). In the immune competent person it rarely poses clinical problems of significance. The most frequently encountered manifestation in older children and adults is a glandular fever-like syndrome. Fever (sometimes as a fever of unknown origin), malaise, pharyngitis, headache, mild diffuse erythematous rash, lymphadenopathy and splenomegaly may also be present. Manifestations usually associated with immunocompromised patients, can be found, but these are rare. They include pneumonitis, meningoencephalitis, Guillain–Barré syndrome, severe thrombocytopenia, haemolysis and hepatitis. Atypical mononucleosis with negative serology for EBV and various immunological epiphenomena such as cryoglobulinaemia, cold agglutinins and positive rheumatoid factor are highly suggestive of CMV disease. In the majority of cases, recovery is usually complete, though deaths have been described.

Infection in pregnancy is a hazard to the foetus and transmission transplacentally or during the second stage of labour (in the case of maternal cervical infections) occurs in approximately 1% of deliveries. It can also be transmitted through breast milk. Transplacental infection causes a substantial risk of the order of 20% for infected neonates for the congenital CMV syndrome characterised by multisystem involvement including particularly microcephaly, mental retardation, chorioretinitis, sensorineural hearing loss, motor disability and hepatosplenomegaly. Risk for disease is governed to an extent by timing of infection during pregnancy and maternal immune status.