Improving sputum culture results for diagnosis of lower respiratory tract by saline washing

Amaç: Alt solunum yolu infeksiyonlarında (ASYİ) Gram boyamanın ve balgam örneklerinin salin ile yıkanmasının katkısının değerlendirilmesi. Metod: Her bir küçük mikroskop alanı (10x) için 10 dan az yassı epitel hücresi içeren tüm örnekler kalitatif ve kantitatif olarak ekildi. Bulgular: ASYİ tanısıyla gönderilen 489 hastadan alınan 620 örnek değerlendirildi. Gram boyamanın duyarlılığı %78.6 , özgüllüğü %82 olarak değerlendirilirken, bu değerler H. influenzae ve S. pneumoniae için %100’ e ulaştı. Kantitatif yöntem kültür pozitifliğini %52’ den % 63.5’ a yükseltti. En sık izole edilen patojenler sırasıyla Haemophilus influenzae, Pseudomonas aeruginosa ve Streptococcus pneumoniae oldu. Sonuç: Ekspoktere balgam örneklerinin toplanması invaziv olmayan bir işlem olup salin ile yıkama sonrası yapılan Gram boyama ve kültür laboratuvar tanısını kolaylaştırabilir. Kültür öncesi Gram boyamada deneyimli bir personel H. influenzae and S. pneumoniae için ön değerlendirmeyi kolaylıkla yapabilir ve kültür sonuçları için gereken 48 saat öncesinde tanıya yardımcı olabilir.

Alt solunum yolu infeksiyonlarının tanısında balgam örneklerinin yıkanmasının kültür sonucuna etkisi

Objective: To evaluate the value of Gram staining and bacteriological culture of sputum by the saline wash method for diagnosis of lower respiratory tract infections (LRTI). Methods: All samples containing fewer than 10 squamous epithelial cells per low power microscopic field (10x) were cultured both directly and quantitatively. Results: 620 sputum specimens from 489 patients clinically diagnosed as having LRTI were evaluated. Sensitivity of Gram stain was 78.6% and specificity was 82%, reaching to 100% for H. influenzae and S. pneumoniae. Quantitative method increased overall culture positivity from 52% to 63.5% of inoculated samples. The three most commonly isolated pathogens were Haemophilus influenzae, Pseudomonas aeruginosa and Streptococcus pneumoniae. Conclusion: The collection of expectorated sputum is a non-invasive process and saline washing and subsequent Gram stain and culture can provide a high diagnostic yield. Initial Gram examination of sputum samples, especially for H. influenzae and S. pneumoniae is advisable when experienced microbiologists interpret the slides, since Gram stain is almost as effective as cultivation and the results are available 48 hours sooner.

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