Coccidioidal pericarditis: a rapid presumptive diagnosis by an in-house antigen confirmed by mycological and molecular methods

1 Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Ceará, Brazil 2 Postgraduate Program in Medical Sciences, Federal University of Ceará, Fortaleza, Ceará, Brazil 3 Postgraduate Program in Medical Microbiology, Federal University of Ceará, Fortaleza, Ceará, Brazil 4 Department of Biological Science, State University of Ceará, Fortaleza, Ceará, Brazil 5 Postgraduate Program in Veterinary Science, State University of Ceará, Fortaleza, Ceará, Brazil 6 Department of Clinical and Toxicological Analysis, Federal University of Ceará, Fortaleza, Ceará, Brazil 7 Department of Microbiology, Immunology and Parasitology, Federal University of São Paulo, São Paulo, Brazil Correspondence Rossana A. Cordeiro ross{at}uece.br Received 3 April 2008 Accepted 22 May 2008 Coccidioidal pericarditis is a condition found in approximately 1–5 % of patients infected by Coccidioides species. It is associated with widely diverse clinical symptoms. This paper reports a case of coccidioidal pericarditis diagnosed by an in-house Coccidioides posadasii antigen and confirmed with mycological and molecular methods. From February to September 2005, the patient suffered from fever, weight loss, a non-productive cough, thoracic pain and tachycardia. He received a positive diagnosis of coccidioidal pericarditis only in October 2005. The macromorphological examination of the culture showed a whitish felt-like colony, which became brownish with age. Preparations in lactophenol cotton blue stain showed hyaline septate hyphae with fragmentation and thin arthroconidia-like structures. Pericardial fluid and sera samples were positive for Coccidioides antibodies by immunodiffusion and ELISA with a C. posadasii in-house antigen preparation. The C. posadasii identification was confirmed by nested PCR of the antigen 2/proline-rich antigen (Ag2/PRA) encoding gene.