Nocardiosis

INTRODUCTION: Nocardiosisis a bacterial infection seen predominantly in patients with altered cell-mediated immunity (CMI). We describe the first case of pulmonary Nocardiosis in an immunocompetent pregnant female presenting as hemoptysis and discuss the pertinent aspects of this patients care.

CASE PRESENTATION: A 32-year-old recently immigrated Chinese woman in the first trimester of pregnancy presented with a 24-hour history of intermittent hemoptysis. She denied fevers, chills, respiratory symptoms and recent tuberculosis exposure although she had a newly positive tuberculin skin test 5 months ago. She had lost 6 pounds in the past two months due to hyperemesis. Her medical history was remarkable for two spontaneous abortions, both during the first trimester, and stress-induced gastritis. Physical examination was unremarkable. Laboratories revealed a hemoglobin of 11.3 g/dL and a D-Dimer of 337. A computed tomography scan of the chest with angiogram (figure 1) revealed ground glass opacifications with peribronchial thickening in the right lower lobe and no pulmonary embolism. Bronchoscopy revealed friable mucosa in the right lower lobe without active bleeding. A work-up for connective tissue disease, HIV and tuberculosis was negative. Her hematocrit remained stable and she was discharged.. Three days later, she presented with recurrent hemoptysis and a new onset of frontal headaches without other neurological symptoms. Her hemoglobin decreased to 9.0g/dL. Magnetic resonance imaging of the brain was negative. The BAL culture returned positive for Nocardia astreroides. She was started on trimethoprim/sulfamethoxazole (TMP-SMX) in consultation with obstetrics and ultimately terminated the pregnancy.

[FIGURE 1 OMITTED]

DISCUSSIONS: Nocardiosis an uncommon infection caused by gram positive, weakly acid fast, filamentous, aerobic actinomycetes in the genus Nocardia. They are relatively slow-growing and may require 5-21 days to exhibit growth. Nocardiosis is typically seen in patients with altered CMI (HIV, iatrogenic immunosuppression, and malignancy), but approximately 36% of patients are immunocompetent. Intact CMI in concert with neutrophil activity is important in containing the infection (Filice et al, JID 1987). In our patient, her sole risk factor was pregnancy. Two previous cases of non-pulmonary nocardia in immunocompetent pregnant women have been described (Braun et al, RID 1991; Kannon et al, J Am Acad Derm 1996). This association, though extremely rare, is plausible. Immunologic changes associated with pregnancy have been designated "pregnancy-associated immune deficiency syndrome" (Weinberg, RID 1984). Increases in hydrocortisone, estrogen, progesterone, and other serum factors may modulate lymphocyte or macrophage synthesis, activation and function during pregnancy leading to depressed CMI.(Weinberg, RID 1984). There is also an imbalance between helper and suppressor T cells (Sridama et al, NEJM 1982) and several studies have shown that total T cell number and cytotoxic lymphocyte activity are both decreased during pregnancy(Davis et al, J Rep Immuno 1998). An important consideration from this case is the overall outcome of the pregancy. The untoward affects of Nocardiosis in human fetuses is not own. However, it is worth noting that Nocardia has been associated with placentitis in cattle, swine and equine populations and has been linked with increasing numbers of losses from late abortions, still-births, prematurity, and early neonatal deaths (Volkmann et al, J S Afr Vet Assoc 2001). Furthermore, antibiotic selection during pregnancy is challenging since the teratogenic potential of most therapeutic agents in humans are largely unkown. TMP/SMX is the agent of choice in treatment of Nocardiosis. However, TMP/SMX has been reported to cause congenital anomalies such as cleft palate in rats, although no cases of human birth abnormalities related to maternal ingestion have been recorded (Chow et al, RID 1985).

CONCLUSION: To our knowledge, this is the first reported case of pulmonary nocardiosis in an immunocompetent pregnant female. This case highlights the importance of bronchoscopy in hemoptysis and the subtle immune deficiency of pregnancy.

DISCLOSURE: Mihwa Pak, None.

Mihwa C. Pak MD * Seth Rivera MD University of California Los Angeles, Los Angeles, CA

COPYRIGHT 2005 American College of Chest Physicians
COPYRIGHT 2005 Gale Group