Faculty Bibliography

Multisystem inflammatory syndrome in children (MIS-C) is thought to follow SARS-CoV-2 infection and presents with fever and multisystem dysfunction. We report three children with suspected MIS-C found to have retropharyngeal edema without evidence of a bacterial etiology. We raise the possibility that an association between MIS-C and retropharyngeal edema exists.

The impact of pre-transplant (SOT) carbapenem-resistant Enterobacterales (CRE) colonization or infection on post-SOT outcomes is unclear. We conducted a multi-center, international, cohort study of SOT recipients, with microbiologically diagnosed CRE colonization and/or infection pre-SOT. Sixty adult SOT recipients were included (liver n=30, hearts n=17). Klebsiella pneumoniae (n=47, 78%) was the most common pre-SOT CRE species. Median time from CRE detection to SOT was 2.32 months (IQR 0.33-10.13). Post-SOT CRE infection occurred in 40% (n=24/60), at a median of 9 days (IQR 7-17), and most commonly due to K. pneumoniae (n=20/24, 83%). Of those infected, 62% had a surgical site infection, and 46% had bloodstream infection. Patients with post-SOT CRE infection more commonly had a liver transplant (16, 67% vs. 14, 39%; P=0.0350) or pre-SOT CRE BSI (11, 46% vs. 7, 19%; P=0.03). One-year post-SOT survival was 77%, and those with post-SOT CRE infection had a 50% less chance of survival vs. uninfected (0.86, 95% CI, 0.76-0.97 vs. 0.34, 95% CI 0.08-1.0, P=0.0204). Pre-SOT CRE infection or colonization is not an absolute contraindication to SOT, and is more common among abdominal SOT recipients, those with pre-SOT CRE BSI, and those with early post-SOT medical and surgical complications.

We report two cases of SARS-CoV-2 infection (COVID-19) in infants presenting with fever in the absence of respiratory distress who required hospitalization for evaluation of possible invasive bacterial infections. The diagnoses resulted from routine isolation and real-time RT-PCR-based testing for SARS-CoV-2 for febrile infants in an outbreak setting.

INTRODUCTION/BACKGROUND:Hypogammaglobulinemia has not been well studied in transplanted children. We quantified plasma immunoglobulin (Ig) and lymphocyte phenotypes among 31 pediatric heart and kidney recipients for two years post-transplant and from 10 non-transplanted children. METHODS:Plasma IgM, IgG, and IgA were quantified by immunoturbidimetric assays, IgG subclasses were quantified by bead-based multiplex immunoassay, and lymphocyte phenotypes were assessed by flow cytometry. RESULTS:Median age at transplant for SOT recipients was similar to that of the control cohort (15 vs. 12.5 years, respectively; p=0.61). Mean plasma IgG and IgM levels for SOT recipients fell significantly below the control cohort means by 1 month post-transplant (p<0.001 for both) and remained lower than control levels at 12-18 months post-transplant. Heart recipients had lower frequencies of CD45RA+CD4+ naïve T lymphocytes relative to kidney recipients. CONCLUSIONS:Hypogammaglobulinemia was prevalent and persistent among pediatric SOT recipients and may be secondary to immunosuppressive medications, as well as loss of thymus tissue and CD45RA+CD4+ T cells in heart recipients. Limitations of our study include but are not limited to small sample size from a single center, lack of samples for all participants at every time point, and lack of peripheral blood mononuclear cell samples for the non-transplanted cohort.

Infectious panniculitis from hematogenous spread is uncommon and usually occurs in immunocompromised patients. Dissemination of gram-positive organisms to the subcutaneous tissue is rare with only several reports of disseminated panniculitis caused by Streptococcal species. We report a case of an immunocompetent 2-year-old boy presenting with diffuse neutrophilic panniculitis arising from methicillin-resistant Staphylococcus aureus septicemia. This case represents a highly atypical manifestation of severe MRSA infection and serves as a reminder to consider MRSA as a cause of disseminated neutrophilic panniculitis, particularly in high-risk populations.