OBJECTIVE: To assess the accuracy of Histoplasma capsulatum variety capsulatum polysaccharide antigen testing for the identification of histoplasmosis relapse in patients with the acquired immunodeficiency syndrome (AIDS). DESIGN: A retrospective study using stored specimens. SETTING: A referral center and several private hospitals. PATIENTS: Twenty episodes of histoplasmosis relapse were evaluated in 17 patients with AIDS from November 1987 to August 1990. Controls included 30 patients with AIDS and histoplasmosis who did not have a relapse during maintenance therapy and who were initially tested during the same week as the patients with relapse. A second control group included seven patients with AIDS and histoplasmosis who were evaluated for relapse on 23 occasions; relapse, however, was excluded on each occasion. MEASUREMENTS: To avoid interassay variability, specimens were tested for H.c. var. capsulatum polysaccharide antigen with the same radioimmunoassay. MAIN OUTCOME MEASURE: The change in the H.c. var. capsulatum polysaccharide antigen level during successful as opposed to unsuccessful maintenance therapy for the prevention of histoplasmosis relapse. MAIN RESULTS: For the 20 episodes of relapse (17 patients), H.c. var. capsulatum antigen levels increased by at least 2 radioimmunoassay units in 12 of 14 serum specimens tested (85.7%; 95% Cl, 57.2% to 98.2%) and in 17 of 18 urine specimens tested (94.4%; Cl, 72.7% to 99.9%). Antigen levels increased in the urine or serum in 1 of 83 specimens (1.2%; CI, 0.03% to 6.6%) obtained on 56 occasions (1.8%; CI, 0.04% to 9.6%) from controls (specificity, 98.2%; CI, 90.4% to 99.96%). In three cases of relapse, antigen levels increased before clinical relapse, antigen levels increased before clinical relapse was suspected. Complement fixation titers increased by at least 2 dilutions in 4 of 11 cases (36.4%; CI, 10.9% to 69.2%) but in 0 of 9 control patients (CI, 0% to 28.3%). CONCLUSION: An increase in H.c. var. capsulatum polysaccharide antigen levels of 2 units or more strongly suggests histoplasmosis relapse. The presence of increasing titers of anti-H.c. var. capsulatum antibodies by complement fixation is less accurate for the diagnosis of relapse.
OBJECTIVE: To assess the accuracy of Histoplasma capsulatum variety capsulatumpolysaccharide antigen testing for the identification of histoplasmosis relapse in patients with the acquired immunodeficiency syndrome (AIDS). DESIGN: A retrospective study using stored specimens. SETTING: A referral center and several private hospitals. PATIENTS: Twenty episodes of histoplasmosis relapse were evaluated in 17 patients with AIDS from November 1987 to August 1990. Controls included 30 patients with AIDS and histoplasmosis who did not have a relapse during maintenance therapy and who were initially tested during the same week as the patients with relapse. A second control group included seven patients with AIDS and histoplasmosis who were evaluated for relapse on 23 occasions; relapse, however, was excluded on each occasion. MEASUREMENTS: To avoid interassay variability, specimens were tested for H.c. var. capsulatumpolysaccharide antigen with the same radioimmunoassay. MAIN OUTCOME MEASURE: The change in the H.c. var. capsulatumpolysaccharide antigen level during successful as opposed to unsuccessful maintenance therapy for the prevention of histoplasmosis relapse. MAIN RESULTS: For the 20 episodes of relapse (17 patients), H.c. var. capsulatum antigen levels increased by at least 2 radioimmunoassay units in 12 of 14 serum specimens tested (85.7%; 95% Cl, 57.2% to 98.2%) and in 17 of 18 urine specimens tested (94.4%; Cl, 72.7% to 99.9%). Antigen levels increased in the urine or serum in 1 of 83 specimens (1.2%; CI, 0.03% to 6.6%) obtained on 56 occasions (1.8%; CI, 0.04% to 9.6%) from controls (specificity, 98.2%; CI, 90.4% to 99.96%). In three cases of relapse, antigen levels increased before clinical relapse, antigen levels increased before clinical relapse was suspected. Complement fixation titers increased by at least 2 dilutions in 4 of 11 cases (36.4%; CI, 10.9% to 69.2%) but in 0 of 9 control patients (CI, 0% to 28.3%). CONCLUSION: An increase in H.c. var. capsulatumpolysaccharide antigen levels of 2 units or more strongly suggests histoplasmosis relapse. The presence of increasing titers of anti-H.c. var. capsulatum antibodies by complement fixation is less accurate for the diagnosis of relapse.
Authors: L J Wheat; G Cloud; P C Johnson; P Connolly; M Goldman; A Le Monte; D E Fuller; T E Davis; R Hafner Journal: Antimicrob Agents Chemother Date: 2001-08 Impact factor: 5.191
Authors: L Joseph Wheat; Patricia Connolly; Nicholas Haddad; Ann Le Monte; Edward Brizendine; Richard Hafner Journal: Antimicrob Agents Chemother Date: 2002-01 Impact factor: 5.191
Authors: B L Gomez; J I Figueroa; A J Hamilton; B L Ortiz; M A Robledo; A Restrepo; R J Hay Journal: J Clin Microbiol Date: 1997-10 Impact factor: 5.948
Authors: Brahm H Segal; Raoul Herbrecht; David A Stevens; Luis Ostrosky-Zeichner; Jack Sobel; Claudio Viscoli; Thomas J Walsh; Johan Maertens; Thomas F Patterson; John R Perfect; Bertrand Dupont; John R Wingard; Thierry Calandra; Carol A Kauffman; John R Graybill; Lindsey R Baden; Peter G Pappas; John E Bennett; Dimitrios P Kontoyiannis; Catherine Cordonnier; Maria Anna Viviani; Jacques Bille; Nikolaos G Almyroudis; L Joseph Wheat; Wolfgang Graninger; Eric J Bow; Steven M Holland; Bart-Jan Kullberg; William E Dismukes; Ben E De Pauw Journal: Clin Infect Dis Date: 2008-09-01 Impact factor: 9.079
Authors: B L Gómez; J I Figueroa; A J Hamilton; S Diez; M Rojas; A Tobón; A Restrepo; R J Hay Journal: J Clin Microbiol Date: 1999-03 Impact factor: 5.948