Pneumocystis cartinzz pneumonia

Although unusual, focal upper zone air space opacification and cyst formation in Pneumocystis carinni pneumonia and HIV infection can occur and may mimic "classical" tuberculosis. (Thorax 1993;48:869-870) Pneumocystis carinii pneumonia (PCP) is the most common HIV related pulmonary infection in both Great Britain and the USA. We report a patient with upper zone opacification and cavitatory disease caused by PCP in HIV disease mimicking "classical" tuberculosis. This is clinically important as tuberculosis is a major infectious pulmonary complication of HIV infection. Because of large overlap of the clinical and radiological signs in HIV related conditions, it is important to reach a definitive diagnosis in HIV infection. Department of Radiology, King's College Hospital, Denmark Hill, London, SES 9RS N C Cowan Department of Thoracic Medicine, King's Coilege School ofMedicine and Dentistry, Bessemer Road, London SE5 9PJ J Moxham Reprint requests to: Professor J Moxham Received 26 May 1992 Returned to authors 29 July 1992 Revised version received 14 October 1992 Accepted 20 October 1992 Case report A 37 year old man presented with a four month history of a non-productive cough, progressive exertional dyspnoea, and night sweats. Recent travel abroad had included a four month visit to Florida, USA. The patient looked well. Small lymph nodes were palpable in the left axilla. The presentation chest radiograph showed bilateral diffuse upper zone airspace opacification with widespread cavitation. Both hila were elevated but there was no hilar lymphadenopathy or pleural effusion (fig 1). A preliminary diagnosis of tuberculosis was made and antituberculosis chemotherapy was started. Results of further investigations at presentation were: Hb 109 g/dl, WBC 6-3 x 109/1, granulocytes 4.7 x 109/1, lymphocytes 1.3 x 109/1, platelets 347 x 1 09/l. Urea and electrolyte levels and liver function test results were normal. The CD4 count was 123/mm3 (410-1540/mm3), and the CD8 count 728/mm3 (230-1100/mm3). The patient was HIV antibody positive. A bronchoscopy was performed but no acid fast bacilli, P carinii or other organisms were identified in bronchial washings. Despite antituberculosis chemotherapy the condition of the patient deteriorated rapidly over the following five days. He developed a high swinging pyrexia, tachycardia and Figure 1 Presentation posteroanterior chest radiograph showing bilateral diffuse upper zone airspace opacification combined with subde cystic change. tachypnoea, with marked central cyanosis and hypoxia (Sao, on air 66%). The chest radiograph now showed an increase in the density and extent of the airspace opacification involving the upper and mid zones of both lungs. A further bronchoscopy with bronchoalveolar lavage was performed. The patient was considered too ill for transbronchial biopsy. The endobronchial mucosa appeared normal and no organisms were identified in the bronchial washings. An open lung biopsy was therefore performed and histological examination showed an interstitial pneumonitis in which alveolar septa were extensively infiltrated by mononuclear and plasma cells. In the smaller airways P carinii organisms were seen with Grocott staining. No fungi or acid fast bacilli were identified. Intravenous co-trimoxazole and hydrocortisone were commenced and the antituberculosis chemotherapy stopped. The patient made a gradual recovery over a period of three weeks and was discharged from hospital feeling well. High resolution computed tomographic examination of the thorax performed after treatment showed the size and distribution of the lung cysts (fig 2).