A Case of Legionellosis Detected with Molecular Syndromic Panel and Review of the Literature

Abstract

Legionella pneumophila is an obligate aerobic intracellular bacterium. It stains poorly with Gram staining and appears as a thin, pleomorphic Gram-negative bacillus. The organism grows poorly on routine culture media. It is distributed worldwide and causes both epidemic and sporadic infections. Transmission usually occurs through inhalation of aerosolized water droplets containing the bacteria. Legionella pneumonia is more frequently observed in elderly and immunosuppressed patients and may present as community-acquired or hospital-acquired pneumonia with a severe clinical course. In this report, we present a case of legionellosis diagnosed using a molecular syndromic panel after the lack of response to β-lactam therapy and the presence of extrapulmonary findings raised suspicion of atypical pneumonia. A brief review of the recent literature was also conducted.

Keywords

• Legionella pneumophila
• pneumonia
• polymerase chain reaction

Moleküler Sendromik Panel ile Tespit Edilen Bir Lejyonelloz Olgusu ve Literatür Taraması

Abstract

L.pneumophila zorunlu aerob, hücre içi bir bakteridir. Gram boyası ile zayıf boyanır ve ince, pleomorfik Gram-negatif basil şeklinde görülür.Etken, rutin kültür besiyerlerinde zayıf ürer. Dünya genelinde yaygın olarak bulunur ve hem salgın hem de sporadik enfeksiyonlara neden olabilir. Bulaş genellikle bakteriyi içeren aerosolize su damlacıklarının inhalasyonu yoluyla gerçekleşir. Legionella pnömonisi daha sık yaşlı ve immünsüprese hastalarda görülür ve ağır klinik seyirli toplum kökenli veya hastane kökenli pnömoni şeklinde ortaya çıkabilir. Bu çalışmada, β-laktam tedavisine yanıt alınmaması ve ekstrapulmoner bulguların atipik pnömoni şüphesini artırması üzerine moleküler sendromik panel ile tanı konulan bir lejyonelloz olgusu sunulmaktadır. Ayrıca güncel literatür kısaca gözden geçirilmiştir.

Keywords

• Legionella pneumophila
• pnömoni
• polimeraz zincir reaksiyonu

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