Usefulness of Q-Probe PCR in Detecting Macrolide-Resistant Mycoplasma pneumoniae Infection in Children.

To investigate the usefulness of quenching probe polymerase chain reaction (Q-probe PCR) for the detection of macrolide-resistant Mycoplasma pneumoniae (MP), we retrospectively analyzed the clinical course of 21 children with MP infection. The rate of macrolide-resistant MP was 66.7%. The duration of pyrexia after the initial antibiotic treatment was longer in patients with macrolide-resistant MP infection than in those with macrolide-sensitive MP infection. The duration of pyrexia after Q-probe PCR was not significantly different between patients with macrolide-resistant and -sensitive MP infection. Antibiotic use based on qPCR may reduce the duration of pyrexia. Q-probe PCR is useful in determining the appropriate antibiotics and improves the clinical course of MP infections.

Serum free carnitine levels in children with Kawasaki disease.

BACKGROUND: Carnitine plays an essential role in the transfer of long-chain fatty acids to the mitochondria for ß-oxidation. No study has characterized carnitine in children with Kawasaki disease (KD). The objective of this study was to elucidate the characteristics of serum free carnitine (FC) in hospitalized pediatric patients with KD. METHODS: We retrospectively analyzed 45 patients with KD in whom serum FC levels were measured. We investigated the clinical and laboratory parameters before intravenous immunoglobulin was administered, including serum FC levels, according to the response to intravenous immunoglobulin (IVIG). We also analyzed the relationship among serum FC, laboratory data, and clinical variables. RESULTS: IVIG was effective in 33 children (responders) and was ineffective in 12 children (non-responders). Serum FC levels were higher in non-responders than in responders: 35.3 µmol/L (range, 26.8-118.4 µmol/L) vs 31.4 µmol/L (range, 20.9-81.2 µmol/L), P <0.05. FC levels before IVIG in 80% of responders were below the normal range. The levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin, and FC were higher in non-responders than in responders. FC levels were correlated with AST (R2 = 0.364, P = 0.0015) and ALT (R2 = 0.423, P < 0.001) levels. CONCLUSIONS: Free carnitine levels were elevated in some patients with KD, especially in those who were refractory to IVIG. Additionally, FC levels in children with KD correlated with ASL and ALT levels.

Usefulness of brain natriuretic peptide to distinguish Kawasaki disease from cervical lymphadenitis.

BACKGROUND: Cervical lymphadenitis (CL) cannot be easily distinguished from Kawasaki disease (KD). We therefore explored whether brain natriuretic peptide (BNP) levels are useful in this context. METHODS: We retrospectively analyzed 14 children with CL and 177 children with KD. Patients with KD were divided into three groups according to their clinical symptoms at hospitalization - 97 patients had typical KD, 35 had node-first KD (NFKD), and 45 had KD without lymphadenopathy. We reviewed data on clinical and laboratory parameters, including serum BNP levels, at hospitalization together with factors that might distinguish KD from CL. RESULTS: Patients with CL were older than those with KD. Serum BNP levels were higher in all the KD groups than in the CL group. Multivariate logistic regression analyses indicated that higher BNP levels were associated with NFKD (odds ratio: 1.12, 95% confidence interval: 1.01-1.25). The receiver operating characteristic curve yielded a BNP cutoff of 18.3 pg/mL, with a sensitivity of 0.680, a specificity of 0.857, and an area under the curve of 0.806 (95% confidence interval: 0.665-0.947). CONCLUSIONS: Serum BNP levels can be used to distinguish KD from CL, especially in patients with NFKD.

Procalcitonin as a Biomarker of Unresponsiveness to Intravenous Immunoglobulin for Kawasaki Disease.

OBJECTIVE: To investigate the usefulness of procalcitonin (PCT) as predictive factors of intravenous immunoglobulin (IVIG)-resistant Kawasaki disease patients. METHODS: We retrospectively analyzed the laboratory data from 215 children with Kawasaki disease treated with IVIG from 2014 to 2019. We analyzed the clinical and laboratory parameters just before the IVIG including serum levels of PCT with respect to the IVIG response. RESULTS: Eventually, 127 patients were analyzed. The median age was 2.4 years. IVIG was effective in 108 children (responders) and was ineffective in 19 (non-responders). Serum PCT concentration was higher in non-responders than those of responders (P < 0.001). Multivariate logistic regression analyses indicated that higher PCT concentration (odds ratio 1.34, 95% confidence interval 1.10-1.64) were associated with IVIG resistance. Analyses of the receiver operating characteristic curve showed that the cutoff value of PCT 2.18 ng/mL had 46.4% of sensitivity and 93.9% of specificity. Receiver operating characteristic analysis yielded an area under the curve of 0.82 (0.72-0.92) to predict IVIG resistance. CONCLUSIONS: Serum PCT value can be an excellent biomarker for predicting unresponsiveness to IVIG with a good discriminatory ability as well as the existing prediction scores.

White Blood Cell and Neutrophil Counts and Response to Intravenous Immunoglobulin in Kawasaki Disease.

We explored parameters to predicting the efficacy of intravenous immunoglobulin (IVIG) therapy for patients with Kawasaki disease (KD). We retrospectively analyzed the laboratory data of 77 children with KD treated with IVIG. Data obtained before and within 24 hours after IVIG therapy were compared between responders and nonresponders. The white blood cell (WBC) and neutrophil counts were significantly lower in responders than nonresponders within 24 hours after IVIG. The areas under the receiver operating characteristics curves of the WBC and neutrophil counts were 0.846 and 0.754, respectively. The WBC and neutrophil counts differed significantly between responders and nonresponders (the latter developed recurrent pyrexia after transient fever resolution). In conclusion, WBC and neutrophil counts within 24 hours after IVIG usefully predict the efficacy of IVIG therapy for those with KD, and identify nonresponders to such therapy.

A combination therapy of whole lung lavage and GM-CSF inhalation in pulmonary alveolar proteinosis.

Systemic and inhalation therapy of granulocyte-macrophage colony-stimulating factor (GM-CSF) is usually effective in controlling autoimmune pulmonary alveolar proteinosis (PAP), but some cases are refractory to GM-CSF therapy and subjected to whole lung lavage (WLL). A 9-year-old girl developed severe respiratory failure due to autoimmune PAP was treated with inhalational 250 microg of GM-CSF daily, however, it was ineffective. Unilateral WLL was performed three times and subsequent GM-CSF inhalation therapy yielded marked physiological and radiological improvement and was continued for 1 year.