Contributed by Davsheen Bedi, MD and Sarah Wheeler, PhD, FACB, CC (NRCC)
A 25-30 year old female from Central Africa presented to the emergency department with chief complaints of fever, productive cough, night sweats and weight loss in the last 2 months. She also had two episodes of hemoptysis. There was no peripheral lymphadenopathy on examination. Patient had no known tuberculosis contacts. Patient gave a history of volunteering and visiting hospitals on weekends in her country of origin. She did not have any history of high-risk behavior or sexually transmitted diseases. She recalled being tested for Human Immunodeificiency Virus (HIV) in the past few years and was found to be negative. Patient's total leukocyte count was within normal reference range for the days of stay in the hospital, with low lymphocytes (Table 1).
Various tests to rule out infectious causes were performed. Respiratory infections were the first differential with this presentation and so the respiratory viral panel (Respiratory Syncytial Virus (RSV), Influenza A and B), Legionella urinary antigen and Streptococcus pneumoniae antigen were ordered. The chest X-ray of the patient showed extensive left sided pneumonia with areas of necrosis and a large cavity in the left upper lobe. Quantiferon TB Gold plus test was ordered and resulted as Indeterminate (Table 2). Being from an endemic area for malaria, blood parasite smear was also performed. She was also tested for HIV, Hepatitis B Virus (HBV) and Hepatitis C Virus (HCV) in the present visit.
The patient's symptoms of fever, cough and weight loss, and abnormal chest X-ray findings increased clinical suspicion for tuberculosis (TB) despite the indeterminate Quantiferon testing. Additionally, the patient's history of travel to a tuberculosis endemic area prompted further confirmatory tests for tuberculosis and so sputum was sent for Acid Fast Bacilli (AFB) staining, TB Polymerase chain reaction (TB PCR) and culture.