Primary multifocal tuberculous osteomyelitis with involvement of the ribs.

Two cases of primary multifocal tuberculous osteomyelitis with involvement of the rib cage are presented. The lungs were normal and the appearance of the skeletal lesions did not suggest tuberculosis. These lesions were predominantly lytic, with minimal soft tissue involvement. Tuberculosis should be high in the differential diagnosis of multiple destructive bone lesions, especially in patients from regions where tuberculosis is endemic.

Hemangiopericytoma of the lacrimal sac.

Hemangiopericytoma (HPCT) rarely originates in the lacrimal sac; 7 cases have been reported previously and only 1 contained an ultrastructural study. In this article we report an additional case and review the previous reports. While the initial biopsy specimen showed nonspecific cytologic abnormalities, light and electron microscopic studies on the subsequently excised tumor demonstrated that it had a structure characteristic of HPCT. The onset of lacrimal sac HPCT occurs in a younger age group than that of HPCT of other orbital locations. The tumor may recur locally but, to our knowledge, never has been reported to metastasize from a sac location. The treatment goal is complete surgical excision.

AIDS-related airway disease.

To our knowledge, the importance of airway disease in HIV-positive patients has been infrequently noted. This deficit likely reflects a combination of factors including lack of familiarity with recent changes in clinical and epidemiologic patterns of pulmonary manifestations of HIV infection and documented limitations of chest radiography for identifying and differentiating airway disease from other causes of pulmonary disease in HIV-positive patients. Familiarity with the imaging findings for these various entities should facilitate prompt diagnosis and treatment. The accuracy of CT in detecting airway disease [55-59] is well established and should be of value in excluding more common diseases that may be initially confused with airway abnormalities [60, 61]. Small airways disease, in particular, which may be occult or mimic an interstitial infiltrate on chest radiography, can be recognized with CT as likely representing infectious bronchitis or bronchiolitis. Patients with findings suggesting bacterial infections may benefit from empiric antibiotic therapy. CT also may be valuable for differentiating between various noninfectious pulmonary diseases, allowing a presumptive diagnosis of parenchymal Kaposi's sarcoma in the appropriate clinical context. In distinction, by detecting localized endobronchial or parenchymal abnormalities in patients with mycobacterial or fungal infections or lymphoma, CT may be valuable for deciding between various invasive methods of obtaining either histologic or bacteriologic diagnoses.

Unusual lymphoproliferative disorders in nine adults with HIV or AIDS: CT and pathologic findings.

PURPOSE: To identify characteristic computed tomographic (CT) findings in unusual pulmonary lymphoproliferative disorders seen in adults with the human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS). MATERIALS AND METHODS: The authors retrospectively reviewed the CT scans and pathologic specimens from nine patients with pulmonary lymphoproliferative disorders. CT scans were evaluated for nodules, reticulation, areas of ground-glass attenuation, consolidation, and bronchial disease. Changes seen in pathologic specimens were classified as consistent with classic lymphocytic interstitial pneumonitis (LIP), mucosa-associated lymphoid tissue lymphoma (MALTOMA), or atypical lymphoproliferative disorder (ALD). Immunopathologic results were reviewed when available. RESULTS: Eight patients had AIDS. Five patients had classic LIP. One patient had MALTOMA, and three patients had ALD. Altogether, 2-4-mm-diameter nodules were the predominant CT finding in eight patients; these were peribronchovascular in four patients. The presence of interstitial nodules correlated with the pathologic finding of nodular disease in seven patients. CONCLUSION: Familiarity with these AIDS-related disorders and their CT appearance should assist in the differential diagnosis.

Granulomatous Pneumocystis carinii pneumonia in three patients with the acquired immune deficiency syndrome.

Pneumocystis carinii pneumonia is a frequent manifestation of the acquired immune deficiency syndrome (AIDS). It usually presents radiologically as diffuse bilateral infiltrates and histologically as a foamy, eosinophilic intra-alveolar exudate containing the organisms' cysts. We recently studied two rare cases of P carinii pneumonia presenting as pulmonary nodules on chest x-ray films in two patients with AIDS. The corresponding histologies were a combination of the usual intra-alveolar pattern, with an alveolar and interstitial granulomatous appearance. Pneumocystis carinii was present in both areas and was the only organism found in the tissues examined. A third case presented with the more common radiographic appearance but also had a granulomatous histology. We conclude that P carinii pneumonia should be considered in the differential diagnosis of pulmonary nodules in immunocompromised patients and that pathologists should be aware of the possibility of a granulomatous reaction to this organism.