The performance of serum cryptococcal capsular polysaccharide antigen test, histopathology and culture of the lung tissue for diagnosis of pulmonary cryptococosis in patients without HIV infection

Abstract

BackgroundClinicians may fail to make an early diagnosis of pulmonary cryptococcosis (PC) without HIV infection. Serum cryptococcal capsular polysaccharide antigen (CrAg) test, histopathology and culture of lung tissue play different roles in diagnosis of PC.ObjectiveTo investigate the performance of serum CrAg test, histopathology and culture of the lung tissue in diagnosis of PC without HIV infection.Patients/methodsFrom January 2011 to September 2017, patients with proven PC were recruited from a teaching hospital in southern China. Those patients with HIV infection, PC confirmed by surgery or PC with probable or possible diagnosis were excluded from the study. Latex agglutination test and CrAg lateral flow assay were used for detection of serum CrAg. Lung biopsy and needle aspiration were performed under computed tomography guidance.ResultsEighty-nine patients with proven PC including 41 male (46.1%) and 48 female (53.9%) were enrolled. Fifty-one (57.3%) patients had underlying disease. Positive CrAg test was found in 83 (93.3%) cases. Among six cases with negative CrAg test, PC was confirmed by histology in two cases and positive culture in four cases. The histopathological results of 77 (86.5%) cases revealed cryptococcal granuloma and 12 cases showed chronic inflammation, which was confirmed by positive culture. Among 65 cases, the diseased tissue of 46 (70.8%) cases presented Cryptococcus neoformans in the culture and one case was diagnosed with lung cancer coexisting with PC.ConclusionOur findings showed that serum CrAg test is rapid and sensitive in diagnosing PC, histology is important for confirming PC and culture plays a complementary role. Biopsied lung tissue should be submitted for cultures whenever feasible.

Clinical analysis of 16 cases of pulmonary cryptococcosis in patients with normal immune function

“…Cryptococcus usually infects the lungs, central nervous system, and skin. Pulmonary cryptococcosis (PC) is often misdiagnosed as lung cancer, tuberculosis, or nonspecific lung inflammation due to the lack of specific clinical and imaging findings (3). In the population with normal immune function, the misdiagnosis rate increased significantly.…”

Serology anno 2021—fungal infections: from invasive to chronic

“…all of them have excellent performance [61][62][63][64]. The CrAg titre is useful for the following response to therapy in the CSF, but not in serum (titres fall slowly).…”

“…Overall and specifically for ICU patients, BAL GM detection seems to be superior [37]. However, the optimal cut-off value An overview on how the various assays may be implemented in the clinical routine is given excellence performance [64]. The CrAg titre is useful for the following response to therapy in the CSF, but not in serum.…”

“…False-positive results caused by the presence of rheumatoid factors in the specimen especially in serum CrAg latex in testing serum: first boil and perform pronase treatment (prozone phenomen) [57,64] J o u r n a l P r e -p r o o f…”

<p>False-Negative Serum Cryptococcal Antigen Lateral Flow Immunoassay Result for a Patient with Disseminated Cryptococcal Disease</p>

“…Additionally, the number of pathogens as well as previous use of antifungal agents may influence the culture results. 3 Cryptococcal meningitis (CM) can be diagnosed by microscopy of fresh CSF using India ink staining, which has 100% specificity but only 50% sensitivity depending on cell titers and capsule production. 7 In the early stages, India ink staining results may appear normal, as with the patient in this case.…”