SESSION TYPE: Infectious Disease Cases III
PRESENTED ON: Wednesday, October 24, 2012 at 11:15 AM - 12:30 PM
INTRODUCTION: Idiopathic CD4 lymphocytopenia (ICL) is a rare condition with unknown prevalence (1). Diagnosis is often made during presentation of an opportunistic infection, most commonly Cryptococcus (1) or a non-tuberculous mycobacterial infection (1, 2). We report a case of a cavitary lesion growing Pneumocystis jirovecii in a non-HIV infected patient, who was later diagnosed with idiopathic CD4 lymphocytopenia.
CASE PRESENTATION: A 65-year-old male former smoker presented to his primary care physician for evaluation of a four-month history of worsening dyspnea on exertion and cough productive of blood-tinged sputum. He acknowledged concomitant fevers, chills, sweats, and a twenty-pound weight loss. Chest radiograph demonstrated a left lower lobe infiltrate. He was treated with antibiotics without improvement. Subsequent computed tomography of the thorax demonstrated a large, thick-walled left lower lobe cavitary lesion with septations. Sputum AFB and aerobic cultures and a tuberculin skin test returned negative. Several days later, the patient presented to our Emergency Department with worsening dyspnea and new left sided, respirophasic chest pain. Oxyhemoglobin saturation on ambient air was 82%. Laboratory testing revealed a mild leukocytosis (12,900) with a left shift. Repeat chest radiograph demonstrated a left sided pnemothorax and bilateral lower lobe opacities. Broad spectrum antibiotics were initiated and emergent tube thoracostomy was performed. Bronchoscopy demonstrated purulent, bloody-appearing mucus plugs in several segmental bronchi. Aerobic, fungal, and AFB cultures of bronchoalveolar lavage fluid returned negative. Transbronchial biopsies of the left lower lobe identified Pneumocystis by silver stain. Treatment with intravenous trimethoprim-sulfamethoxazole and oral prednisone was initiated.
DISCUSSION: Further investigation revealed no exposure history and no risk factors for human immunodeficiency virus (HIV). HIV status was confirmed by a negative enzyme linked immunosorbent assay (ELISA) test. Absolute CD4 count returned low at 94 (16%). The patient was diagnosed with idiopathic CD4 lymphocytopenia after two additional negative ELISA tests for HIV, separate screening for HIV type 2, and three undetectable HIV viral load titers. He improved with antibiotic and steroid therapy, and long-term Pneumocystis and Toxoplasmosis prophylaxis was initiated.
CONCLUSIONS: This presumably immunocompetent individual presented with a thick-walled cavitation and a spontaneous pneumothorax, an unusual presentation of Pneumocystis infection. Idiopathic CD4 lymphocytopenia should be considered in the differential diagnosis of unexplained Pneumocystis, as the incidence and prevalence of idiopathic CD4 lymphocytopenia remains unknown (1).
1) Smith, D. et. al. Unexplained opportunistic infections and CD4 T-lymphocytopenia without HIV infection. 1993 N Engl J Med;328:373-379
2) Spira, T. et. al. Idiopathic CD4 T-lymphocytopenia. 1993 N Engl J Med;328:386-392
DISCLOSURE: The following authors have nothing to disclose: Aamir Gilani, Jamie Bessich
No Product/Research Disclosure InformationDartmouth-Hitchcock Medical Center, Lebanon, NH