TABLE 1.

Clinical and laboratory findings for patients with falsely positive Histoplasma UAg values of <0.6 ng/ml^a

Patient no.	Age (yr)/sex	Presenting symptom(s)	Comorbidity(ies)/immune status	Radiologic findings at presentation	Other microbiology findings	Final diagnosis	Antifungals started?
1	46/F	Fever; new DVT/PICC	Sacral OM 3 months prior	N/A	Enterobacter cloacae BSI	E. cloacae BSI	No
2	67/M	Weight loss, dysphagia	Coronary/peripheral artery disease	Hepatosplenomegaly	H. capsulatum yeast CF (1:16)	Sarcoidosis	No
3	73/M	Incidental cavitary lesion	B-cell lymphoma on chemotherapy	Left lung cavitary lesion	N/A	Unclear etiology	Empirical fluconazole
4	27/F	Fever, cough	None	Bilateral lung infiltrates	N/A	Community-acquired pneumonia	No
5	70/F	Respiratory failure	Lung carcinoma on chemotherapy	Bilateral lung infiltrates	Blastomyces UAg positive (2.19 ng/ml)	Disseminated blastomycosis	Itraconazole
6	81/M	Pancytopenia, noncaseating granuloma in BM	Coronary artery disease	Splenomegaly	H. capsulatum yeast CF (1:16); H. capsulatum ID; M band Coccidioides CF (1:2)	Granulomatous disease, secondary to sarcoidosis	No
7	74/F	Persistent pulmonary infiltrates	Hypertension	Bilateral lung infiltrates	Coccidioides IgG ID positive and CF (1:8)	Coccidioidomycosis	Fluconazole
8	74/M	Elevated ESR	RA on methotrexate	Nodular lung infiltrates	Blastomyces recovered from BAL fluid	Pulmonary blastomycosis	Itraconazole
9	37/M	Lymphadenopathy	Unclear	N/A	Coccidioides spherule identified from lymph node biopsy specimen	Coccidioides lymphadenopathy	Fluconazole
10	55/M	Fever, fatigue	Stem cell transplant on prednisone	Bilateral ground-glass infiltrates	Pseudomonas isolated from sputum	Unclear etiology, initiated on ciprofloxacin	No
11	66/F	Incidental CT finding	Remote esophageal cancer	Upper lobe nodules	N/A	Unclear etiology	No
12	11/F	Fever, dry cough	None	Cavitary infiltrate	Blastomyces EIA and UAg positive	Pulmonary blastomycosis	Itraconazole

^aAbbreviations: M, male; F, female; RA, rheumatoid arthritis; BM, bone marrow; DVT/PICC, deep vein thrombosis/peripherally inserted central catheter; ID, immunodiffusion; CF, complement fixation; OM, osteomyelitis; BSI, bloodstream infection; WL, weight loss; BAL, bronchoalveolar lavage; ESR, erythrocyte sedimentation rate; HA, headache; CT, computed tomography; N/A, not applicable.