Criteria for each item in the six-point scoring system.
Abstract
Legionella pneumophila is one of the important pathogens in community-acquired (CAP) and hospital-acquired pneumonia that can cause severe pneumonia. Early diagnosis and treatment of Legionella pneumonia (LP) are essential because inappropriate therapy for Legionella pneumonia has been reported to worsen the prognosis. The most frequently identified causative pathogen of Legionella pneumonia is Legionella pneumophila serogroup 1. Legionella pneumonia due to non-Legionella pneumophila serogroup 1 is seen in 20% of cases. In diagnosing Legionella pneumonia caused by non-Legionella pneumophila serogroup 1, the urinary antigen test is usually negative; therefore, we need to suspect Legionella pneumonia by clinical information such as symptoms, vital signs, laboratory findings, and radiological findings. Based on our previous report, Legionella pneumonia due to non-Legionella pneumophila serogroup 1 was a mild to severe pneumonia. In addition, in about half of the patients, we could not suspect Legionella pneumonia using a six-point scoring system, which is one of the diagnostic scoring systems. Recently, a new urinary antigen test kit that could theoretically diagnose Legionella pneumonia due to non-Legionella pneumophila serogroup 1 was released in Japan. This can help in early diagnosis of Legionella pneumonia, including the one caused by non-Legionella pneumophila serogroup 1.
Keywords
- diagnosis
- Legionella pneumonia
- Legionella pneumophila serogroup 1
- non-Legionella pneumophila serogroup 1
- urinary antigen
1. Introduction
The most frequently identified causative microorganism of
The gold standard in the diagnosis of LP is the identification of
Currently, a urinary antigen test that detects soluble antigens is widely used for diagnosing LP in daily clinical practice worldwide. This diagnostic method is very useful because the examination procedure is simple and the results are known quickly. In a systematic review and meta-analysis, Shimada et al. reported that the specificity of the
The diagnostic key for LP due to non-
2. Legionella pneumonia due to non-Legionella pneumophila serogroup 1
2.1 Previous reports
In earlier studies, LP due to non-
There have been many case reports of LP caused by non-
2.2 Diagnostic scoring system
We cannot rule out LP by a negative result of the urinary antigen test because the sensitivity of this test is not very good. To diagnose LP with a negative urinary antigen test, we need to suspect it based on the symptoms, vital signs, laboratory examinations, and radiological findings.
In 1998, Cunha advocated a diagnostic scoring system for LP called the “Winthrop-University Hospital (WUH) criteria” [24]. The WUH criteria comprised 15 clinical findings and seven laboratory findings, and it was therefore thought to be too complicated to use in the daily clinical practice.
In 2009, Fiumefreddo proposed a six-point scoring system for predicting LP [25], and this scoring system was validated by Haubitz [26]. This scoring system comprised one symptom, one vital sign, and four laboratory findings. The criteria for the six items are listed in Table 1. A score ≥5 had very high specificity (99.0%) and a high positive predictive value (17.4%), whereas a score <2 had high sensitivity (94.4%) and a high negative predictive value (99.6%). In our previous reports [21], using a cutoff value of ≥2 points, the sensitivity of this scoring system was 54.5% for non-
Temperature | >39.4°C |
C-reactive protein | >187 mg/L |
Lactate dehydrogenase | >225 mmol/L |
Platelets | <171 × 109/L |
Serum sodium | <133 mmol/L |
Unproductive cough |
3. Future perspective
Patients with LP have a worse prognosis if they are not treated with appropriate antibiotic therapy as soon as possible. Some patients with LP due to
In February 2019, Asahi Kasei Pharma Corporation released a urinary antigen test kit that could diagnose LP due to non-
In the future, we expect that early diagnosis of LP including non-
4. Conclusion
LP due to non-
Acknowledgments
The authors would like to thank all of our colleagues who recruited and treated the patients. They would also like to thank Hiroyuki Fujii from the Department of Clinical Laboratory, Ohara Healthcare Foundation, Kurashiki Central Hospital, for performing sputum culture for
References
- 1.
Cunha BA, Burillo A, Bouza E. Legionnaires’ disease. The Lancet. 2016; 387 :376-385 - 2.
Edelstein PH. Legionella . In: Versalovic J, Carroll KC, Funke G, Jorgensen JH, Landry ML, Warnock DW, editors. Manual of Clinical Microbiology. 10th ed. Washington, DC: American Society of Microbiology Press; 2011. pp. 770-785 - 3.
Amemura-Maekawa J, Kura F, Helbig JH, Chang B, Kaneko A, Watanabe Y, et al. Working Group for Legionella in Japan. Characterization of Legionella pneumophila isolates from patients in Japan according to serogroups, monoclonal antibody subgroups and sequence types. Journal of Medical Microbiology. 2010;59 :653-659 - 4.
Helbig JH, Bernander S, Castellani Pastoris M, Etienne J, Gaia V, Lauwers S, et al. Pan-European study on culture-proven legionnaires’ disease: Distribution of Legionella pneumophila serogroups and monoclonal subgroups. European Journal of Clinical Microbiology & Infectious Diseases. 2002;21 :710-716 - 5.
Ishida T, Hashimoto T, Arita M, Ito I, Osawa M. Etiology of community-acquired pneumonia in hospitalized patients: A 3-year prospective study in Japan. Chest. 1998; 114 :1588-1593 - 6.
Saito A, Kohno S, Matsushima T, Watanabe A, Oizumi K, Yamaguchi K, et al. Prospective multicenter study of the causative organisms of community-acquired pneumonia in adults in Japan. Journal of Infection and Chemotherapy. 2006; 12 :63-69 - 7.
von Baum H, Ewig S, Marre R, Suttorp N, Gonschior S, Welte T, et al. Competence Network for Community Acquired Pneumonia Study Group. Community-acquired Legionella pneumonia: New insights from the German competence network for community acquired pneumonia. Clinical Infectious Diseases. 2008;46 :1356-1364 - 8.
Cillóniz C, Ewig S, Polverino E, Marcos MA, Esquinas C, Gabarrús A, et al. Microbial aetiology of community-acquired pneumonia and its relation to severity. Thorax. 2011; 66 :340-346 - 9.
Mandell LA, Wunderink RG, Anzueto A, Bartlett JG, Campbell GD, Dean NC, et al. Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clinical Infectious Diseases. 2007; 44 (Suppl 2):S27-S72 - 10.
Ishiguro T, Takayanagi N, Yamaguchi S, Yamakawa H, Nakamoto K, Takaku Y, et al. Etiology and factors contributing to the severity and mortality of community-acquired pneumonia. Internal Medicine. 2013; 52 :317-324 - 11.
Ishida T, Tachibana H, Ito A, Tanaka M, Tokioka F, Furuta K, et al. Clinical characteristics of severe community-acquired pneumonia among younger patients: An analysis of 18 years at a community hospital. Journal of Infection and Chemotherapy. 2014; 20 :471-476 - 12.
Viasus D, Di Yacovo S, Garcia-Vidal C, Verdaguer R, Manresa F, Dorca J, et al. Community-acquired Legionella pneumophila pneumonia: A single-center experience with 214 hospitalized sporadic cases over 15 years. Medicine (Baltimore). 2013;92 :51-60 - 13.
Olsen CW, Elverdal P, Jørgensen CS, Uldum SA. Comparison of the sensitivity of the Legionella urinary antigen EIA kits from Binax and Biotest with urine from patients with infections caused by less common serogroups and subgroups ofLegionella . European Journal of Clinical Microbiology & Infectious Diseases. 2009;28 :817-820 - 14.
Faris B, Faris C, Schousboe M, Heath CH. Legionellosis from Legionella pneumophila serogroup 13. Emerging Infectious Diseases. 2005;11 :1405-1409 - 15.
Ito A, Ishida T, Tachibana H, Ito Y, Takaiwa T, Fujii H, et al. A case of community-acquired pneumonia due to Legionella pneumophila serogroup 9 in which initial treatment with single-dose oral azithromycin appeared useful. Japanese Journal of Infectious Diseases. 2017;70 :660-662 - 16.
Chen CY, Chen KY, Hsueh PR, Yang PC. Severe community-acquired pneumonia due to Legionella pneumophila serogroup 6. Journal of the Formosan Medical Association. 2006;105 :256-262 - 17.
Lück PC, Schneider T, Wagner J, Walther I, Reif U, Weber S, et al. Community-acquired legionnaires’ disease caused by Legionella pneumophila serogroup 10 linked to the private home. Journal of Medical Microbiology. 2008;57 :240-243 - 18.
Furugen M, Koide M, Baba M, Sato Y, Teruya H, Naha Y, et al. Legionella pneumonia caused byLegionella pneumophila serogroup 2: Second case report in Japan. Journal of Infection and Chemotherapy. 2008;14 :161-165 - 19.
Kawanami T, Yatera K, Fukuda K, Yamasaki K, Kunimoto M, Nagata S, et al. Diagnosis of fulminant pneumonia caused by Legionella pneumophila serogroup 8 with the sequence analysis of the 16S rRNA gene. The Tohoku Journal of Experimental Medicine. 2011;225 :65-69 - 20.
Grottola A, Forghieri F, Meacci M, Fabio A, Pozzi L, Marcheqiano P, et al. Severe pneumonia caused by Legionella pneumophila serogroup 11, Italy. Emerging Infectious Diseases. 2012;18 :1911-1913 - 21.
Ito A, Ishida T, Washio Y, Yamazaki A, Tachibana H. Legionella pneumonia due to non-Legionella pneumophila serogroup 1: Usefulness of the six-point scoring system. BMC Pulmonary Medicine. 2017;17 :211 - 22.
Fine MJ, Auble TE, Yealy DM, Hanusa BH, Weissfeld LA, Singer DE, et al. A prediction rule to identify low-risk patients with community-acquired pneumonia. New England Journal of Medicine. 1997; 336 :243-250 - 23.
Lim WS, van der Eerden MM, Laing R, Boersma WG, Karalus N, Town GI, et al. Defining community acquired pneumonia severity on presentation to hospital: An international derivation and validation study. Thorax. 2003; 58 :377-382 - 24.
Cunha BA. Clinical features of legionnaires’ disease. Seminars in Respiratory Infections. 1998; 13 :116-127 - 25.
Fiumefreddo R, Zaborsky R, Haeuptle J, Christ-Crain M, Trampuz A, Steffen I, et al. Clinical predictors for Legionella in patients presenting with community-acquired pneumonia to the emergency department. BMC Pulmonary Medicine. 2009;9 (4). DOI: 10.1186/1471-2466-9-4 - 26.
Haubitz S, Hitz F, Graedel L, Batschwaroff M, Wiemken TL, Peyrani P, et al. Ruling out Legionella in community-acquired pneumonia. The American Journal of Medicine. 2014;127 :1010.e11-1010.e19