Improved Diagnostics Help to Identify Clinical Features and Biomarkers That Predict Mycoplasma pneumoniae Community-acquired Pneumonia in Children

Abstract

Background. There are no reliable signs or symptoms that differentiate Mycoplasma pneumoniae (Mp) infection in communityacquired pneumonia (CAP) from other etiologies. Additionally, current diagnostic tests do not reliably distinguish between Mp infection and carriage. We previously determined that the measurement of Mp-specific immunoglobulin M antibody-secreting cells (ASCs) by enzyme-linked immunospot assay allowed for differentiation between infection and carriage. Using this new diagnostic test, we aimed to identify clinical and laboratory features associated with Mp infection.Methods. This is a prospective cohort study of children, 3-18 years of age, with CAP from 2016 to 2017. Clinical features and biomarkers were compared between Mp-positive and -negative groups by Mann-Whitney U test or Fisher exact test, as appropriate. Area under the receiver operating characteristic curve (AUC) differences and optimal thresholds were determined by using the DeLong test and Youden J statistic, respectively.Results. Of 63 CAP patients, 29 were Mp-positive (46%). Mp positivity was statistically associated with older age (median, 8.6 vs 4.7 years), no underlying disease, family with respiratory symptoms, prior antibiotic treatment, prolonged prodromal respiratory symptoms and fever, and extrapulmonary (skin) manifestations. Lower levels of C-reactive protein, white blood cell count, absolute neutrophil count, and procalcitonin (PCT), specifically PCT <0.25 μg/L, were statistically associated with Mp infection. A combination of age >5 years (AUC = 0.77), prodromal fever and respiratory symptoms >6 days (AUC = 0.79), and PCT <0.25 μg/L (AUC = 0.81) improved diagnostic performance (AUC = 0.90) (P = .05).Conclusions. A combination of clinical features and biomarkers may aid physicians in identifying patients at high risk for Mp CAP.

High ratio of C-reactive protein/procalcitonin predicts Mycoplasma pneumoniae infection among adults hospitalized with community acquired pneumonia

“…This difference may be due to the different subjects and different locations of the study. Moreover, in contrast to our findings, Patrick et al recently suggest that a high CRP/PCT ratio (>400 lg/ng) was helpless to predict MP-related CAP in children [8]. This difference may be attributed to the different age compositions of the study populations.…”

“…The increase of PCT contributes to the severity of the systemic bacterial infection and the poor prognosis [7]. Also, higher PCT levels can help to identify MP-CAP and viral CAP [8,9]. However, there are some researches that contradict these beliefs.…”

Predictive and Prognostic Utility of the Serum Level of Resistin-Like Molecule Beta for Risk Stratification in Patients with Community-Acquired Pneumonia

“…However, its role in the development of CAP is unclear. Mycoplasma pneumoniae is a frequent cause of community-acquired respiratory infections in children and adults [ 33 ], but we found the RELM-β level of the Mp − group was significantly higher than that of the Mp + group. Regardless of whether the patient is infected with Mp , the concentration of RELM-β will also increase significantly as the patient’s disease gets worse.…”

Macrolide resistance and molecular typing of Mycoplasma pneumoniae infections during a 4 year period in Spain

“…It has been reported that MP can colonize the nasopharynx for a long time without any clinical manifestation. Meyer Sauteur et al 37 detected MP DNA in 48% of healthy children tested as controls during their study, and Nilsson et al 33 were able to detect MP DNA for 7 weeks after the clinical symptoms, even though the patients were correctly treated with MLs. Further research would be necessary to clarify the impact of carriers in the community on infection transmission.…”