Epidemiology and outcomes of pneumococcal sepsis in children with nephrotic syndrome in a developing country

Pneumococcal carriage and serotype distribution in children with nephrotic syndrome

BACKGROUND

Patients with nephrotic syndrome (NS) are at a higher risk of developing invasive pneumococcal disease (IPD). Pneumococcal carriage studies are helpful tools for detecting potentially infectious serotypes and guiding immunization efforts. Pneumococcal nasopharyngeal colonization is common, and IPD can easily occur in an immunosuppressed state. Limited information is available regarding the frequency of pneumococcal carriage in individuals with NS. The aim of this study was to evaluate pneumococcal carriage and serotype distribution in children with NS.

METHODS

Pneumococcal carriage was detected by real-time PCR assays from nasopharyngeal swab samples from 98 children with NS, and 100 healthy controls. Isolates were serotyped by real-time PCR.

RESULTS

The pneumococcal carriage rate was 44.9% in children with NS. Regarding the recommendation about pneumococcal immunization in children with NS, the vaccination rate was low. Also, non-PCV13 serotypes have been detected in at least 25% of PCV13-vaccinated children. There is no statistically significant difference in total pneumococcal carriage rate, PCV13 serotype carriage rate, or non-PCV13 serotype carriage rate between children with NS and healthy controls (p > 0.05 for all).

CONCLUSIONS

The pneumococcal carriage rate was similar between children with NS and healthy controls. However, because children with NS have an increased risk for IPD, the serotype distribution of children with NS can demonstrate the improved protection offered by new pneumococcal vaccines. Regular monitoring for IPD is crucial for assessing the evolving sero-epidemiology of pneumococcal infections and evaluating the effectiveness of vaccines for children with NS.

Diagnosis of bacterial infection in children with relapse of nephrotic syndrome: a personalized decision-analytic nomogram and decision curve analysis

BACKGROUND

Infections associated with nephrotic relapses (NR) are often managed according to physician preferences. A validated prediction tool will aid clinical decision-making and help in rationalizing antibiotic prescriptions. Our objective was to develop a biomarker-based prediction model and a regression nomogram for the prediction of the probability of infection in children with NR. We also aimed to perform a decision curve analysis (DCA).

METHODS

This cross-sectional study included children (1-18 years) with NR. The outcome of interest was the presence of bacterial infection as diagnosed using standard clinical definitions. Total leucocyte count (TLC), absolute neutrophil count (ANC), quantitative C-reactive protein (qCRP), and procalcitonin (PCT) were the biomarker predictors. Logistic regression was used to identify the best biomarker model, followed by discrimination and calibration testing. Subsequently, a probability nomogram was constructed and DCA was done to determine the clinical utility and net benefits.

RESULTS

We included 150 relapse episodes. A bacterial infection was diagnosed in 35%. Multivariate analysis showed the ANC + qCRP model to be the best predictive model. This model displayed excellent discrimination (AUC: 0.83), and calibration (optimism-adjusted intercept: 0.015, slope: 0.926). A prediction nomogram and web-application was developed. The superiority of the model was also confirmed by DCA in the probability threshold range of 15-60%.

CONCLUSIONS

An ANC-based and qCRP-based internally validated nomogram can be used for the prediction of probability of infection in non-critically ill children with NR. Decision curves from this study will aid in the decision-making of empirical antibiotic therapy, incorporating threshold probabilities as a surrogate of physician preference. A higher resolution version of the Graphical abstract is available as Supplementary information.

Streptococcus pneumoniae meningitis in a child with idiopathic nephrotic syndrome: a case report

BACKGROUND

Children with nephrotic syndrome are at increased risk of infections, including bacterial peritonitis, pneumonia, and cellulitis. However, bacterial meningitis, a potentially life-threatening complication, has not been highlighted as an infectious complication of nephrotic syndrome in recent reviews. We report a very subtle and unusual presentation of bacterial meningitis in a child with nephrotic syndrome, which without a high index of suspicion, would have been missed.

CASE PRESENTATION

A 9-year-old African-American male with a history of steroid-dependent nephrotic syndrome presented to the nephrology clinic for routine follow-up. His medications included mycophenolate mofetil and alternate-day steroids. His only complaint was neck pain and stiffness that the mother attributed to muscle tightness relieved by massage. There was no history of fever, vomiting, headache, photophobia, or altered mental status. On physical examination, he was afebrile (99 °F), but had mild periorbital swelling and edema on lower extremities. He appeared ill and exhibited neck rigidity, and demonstrated reflex knee flexion when the neck was bent. Laboratory evaluation revealed leukocytosis, elevated C-reactive protein, hypoalbuminemia, and proteinuria. Cerebrospinal fluid suggested bacterial meningitis. The patient was treated with ceftriaxone and vancomycin. Both cerebrospinal and blood cultures grew Streptococcus pneumoniae; vancomycin was discontinued. The child completed a 2-week course of ceftriaxone and was discharged home.

CONCLUSIONS

A high index of suspicion is necessary in children with nephrotic syndrome treated with corticosteroids, as symptoms may be masked, and thus, a life-threatening disease be missed. Bacterial meningitis should be highlighted as a serious infection complication in children with nephrotic syndrome.