Cytomegalovirus retinitis is common in adults with AIDS but has been reported infrequently in children with perinatally acquired HIV infection. The cases are presented of two infants with vertically acquired HIV infection who developed disseminated cytomegalovirus infection and retinitis, and who posed difficult management issues. (Arch Dis Child 1995; 72: 54-55 A 4 month old breast fed infant was admitted in respiratory failure after a one week history of cough, tachypnoea, and poor feeding. He required ventilation and a bronchoalveolar lavage demonstrated Pneumocystis carinii pneumonia. HIV-1 antibodies were detected on serological testing; HIV polymerase chain reaction was positive for gag and pol primers, and p24 antigen was detected at a concentration of 95 pg/ml. CD4 count was 0-073X 109/1 (4% of a total lymphocyte count of 1 83X 109/1). He made a good initial recovery after treatment with high dose co-trimoxazole (120 mg/kg/day), methylprednisolone, fluid restriction, and frusemide. Despite being extubated after three days, he still required high concentrations of oxygen via head box and deteriorated when attempts were made to decrease the steroid treatment. Two weeks after admission chest radiography showed persistent bilateral interstitial pneumonitis. Abnormal liver function test results prompted cytomegalovirus screening and early antigen was detected in urine and nasopharyngeal secretions, though not in the buffy coat. Ophthalmological review revealed two white retinal exudates present in the left eye. The larger one was of several disc diameters in size and the smaller was a perivascular lesion (figure).