Streptesti

Streptesti, commonly translated as strep test, is a diagnostic method used to detect Streptococcus bacteria in clinical specimens, most often for suspected Streptococcus pyogenes (group A streptococcus) in throat infections. It encompasses rapid antigen detection tests (RADTs), rapid molecular tests such as PCR-based assays, and traditional culture methods. In practice, a clinician takes a throat swab. RADTs provide results within minutes by detecting Streptococcus-specific antigens; molecular assays also use a throat swab but detect DNA and are typically more sensitive. Culture remains the reference standard but takes 24 to 48 hours.

Interpretation: A positive result indicates the presence of streptococcal bacteria, supporting a bacterial etiology of pharyngitis. A negative RADT does not completely exclude infection, and clinicians may perform culture or repeat testing in children and adolescents, where accuracy matters to prevent rheumatic fever; in adults, a negative RADT may be managed without antibiotics depending on symptoms and guidelines.

Clinical use and limitations: Streptest guides antibiotic decisions, reducing unnecessary antibiotic use for viral infections. Limitations include variable sensitivity and specificity, sample quality, and inability to distinguish colonization from active infection or differentiate among streptococcal groups.

Regulatory and practice notes: Tests are performed in clinical laboratories or at point-of-care settings under regulatory approval. Training and quality control are essential to ensure accuracy. See also strep throat, rapid strep test, throat swab.