INTRODUCTION: Nocardia, an important opportunistic pathogen in many groups of immunocompromised patients, is rare in AIDS patients. Timely diagnosis and appropriate treatment prevents dissemination and improves clinical outcomes. The objectives of our case report are: (1) To discuss a case of pulmonary Nocardiosis in a patient with HIV/AIDS. (2) To emphasize awareness of the possibility of Nocardia sp. as an initial opportunistic pathogens in AIDS patients.
CASE PRESENTATION: A 38 year old African American man was admitted with a 3 week history of shortness of breath and productive cough. Over the prior 4 months he also experienced generalized malaise, 40 pound weight loss, night sweats and subjective fevers. The patient denied smoking, alcohol and recreational drug use. He had not traveled recently and denied sick contacts and animal exposures, but admitted to unprotected heterosexual sexual exposure. Pertinent physical findings were a respiratory rate of 22/minute, oxygen saturation 90% room air, temperature of 98.9°F, decreased pulmonary breath sounds bilaterally with bronchial quality. He had a leukocytosis of 16,000/mm3 with granulocytes 63%, lymphocytes 22% and LDH 483 units/ml. Renal and liver function tests were normal. HIV serology was positive and the absolute CD4 count was 50. Chest x-ray showed bilateral airspace disease, accentuated in right upper lobes with fibro nodular changes and possible cavitation. Blood cultures were negative. The patient was empirically begun on treatment doses of Trimethoprim/sulphamethoxazole (Bactrim) for possible Pneumocystis jirovecii pneumonia pending bronchoscopic diagnosis. Expectorated and induced sputa grew mixed flora and were negative on stain for Pneumocystis and AFB. The patient clinically improved on trimethoprim/sulfamethoxazole. Bronchoscopic specimens were stain negative for AFB, Pneumocystis and viral cytologic changes and grew Nocardia asteroides. The patient was continued on high dose oral trimethoprim/sulfamethoxazole with continued clinical improvement and was discharged from the hospital on that regimen for outpatient follow-up.
DISCUSSIONS: Nocardia species are aerobic actinomycetes, recognized as pathogens particularly in immunosuppressed patients. They remain however uncommon in AIDS patients. This may in part be an incidental benefit of receiving trimethoprim/sulfamethoxazole for Pneumocystis pneumonia prophylaxis. Primary nocardial infection includes pulmonary or cutaneous and/or subcutaneous lesions. Disseminated disease is defined by the identification of nocardial infection in two or more organs. Ninety percent of systemic cases are secondary to N. asteroides complex. Clinical pulmonary presentations may vary and includes acute or chronic pneumonia, lung abscess, or empyema. Delay in the diagnosis and treatment of Nocardia infections risks systemic dissemination and higher mortality. AIDS patients who present with undiagnosed pneumonias prior to starting Pneumocystis prophylaxis with Bactrim, like our patient, may be at increased risk of having Nocardia pulmonary infections as either the primary pulmonary process or as a co-infection with Pneumocystis, Mycobacterium tuberculosis or Mycobacterium avium-intracellulare. In the absence of a diagnosis made on expectorated or induced sputa, bronchoscopic specimens should be obtained for diagnosis and Nocardia infection considered in the differential diagnosis.
CONCLUSION: We present a case of pulmonary nocardiosis as the initial presenting infection in HIV/AIDS. This serves as a reminder of this clinical entity and it's potential clinical response to empiric trimethoprim/methoxazole therapy. In the absence of an etiologic diagnosis and with a chest radiograph that would be atypical of Pneumocystis, despite the apparent clinical response to initial therapy, bronchoscopy yielded the definitive diagnosis. Pursuing a definitive diagnosis is critical to determine the appropriate course of antimicrobial therapy and improve patient survival.
DISCLOSURE: Supriya Mannepalli, No Financial Disclosure Information; No Product/Research Disclosure Information