Human inherited complete STAT2 deficiency underlies inflammatory viral diseases.

STAT2 is a transcription factor activated by type I and III IFNs. We report 23 patients with loss-of-function variants causing autosomal recessive (AR) complete STAT2 deficiency. Both cells transfected with mutant STAT2 alleles and the patients' cells displayed impaired expression of IFN-stimulated genes and impaired control of in vitro viral infections. Clinical manifestations from early childhood onward included severe adverse reaction to live attenuated viral vaccines (LAV) and severe viral infections, particularly critical influenza pneumonia, critical COVID-19 pneumonia, and herpes simplex virus type 1 (HSV-1) encephalitis. The patients displayed various types of hyperinflammation, often triggered by viral infection or after LAV administration, which probably attested to unresolved viral infection in the absence of STAT2-dependent types I and III IFN immunity. Transcriptomic analysis revealed that circulating monocytes, neutrophils, and CD8+ memory T cells contributed to this inflammation. Several patients died from viral infection or heart failure during a febrile illness with no identified etiology. Notably, the highest mortality occurred during early childhood. These findings show that AR complete STAT2 deficiency underlay severe viral diseases and substantially impacts survival.

Long-Acting Antiretroviral Drug Therapy in Adolescents: Current Status and Future Prospects.

Approximately 50% of human immunodeficiency virus (HIV)-infected adolescents fail to achieve complete viral suppression, largely due to nonadherence to their antiretroviral drug regimens. Numerous personal, financial, and societal barriers contribute to nonadherence, which may lead to the development of HIV drug resistance. Long-acting antiretroviral drugs hold the promise of improved adherence because they remove the need for swallowing one or more pills daily. Cabotegravir (an integrase strand transfer inhibitor) and rilpivirine (a non-nucleoside reverse transcriptase inhibitor) can now be intramuscularly co-administered to HIV-infected adolescents every 4-8 weeks if they are virologically suppressed and without resistance mutations to cabotegravir or rilpivirine. Adverse effects are few and non-severe. Widespread use of this complete antiretroviral therapy may be limited by drug costs, need for sites and skilled personnel who can administer the injections, and ethical challenges. Other long-acting medications and new antiretroviral therapy delivery systems are under active investigation and show great promise.

mRNA Coronavirus Disease 2019 Vaccine-Associated Myopericarditis in Adolescents: A Survey Study.

In this survey study of institutions across the US, marked variability in evaluation, treatment, and follow-up of adolescents 12 through 18 years of age with mRNA coronavirus disease 2019 (COVID-19) vaccine-associated myopericarditis was noted. Only one adolescent with life-threatening complications was reported, with no deaths at any of the participating institutions.

Diversity of Cardiac and Gastrointestinal Presentations of Multisystem Inflammatory Syndrome in Children (MIS-C) Associated with COVID-19: A Case Series.

COVID-19 is generally a benign or asymptomatic infection in children, but can occasionally be severe or fatal. Delayed presentation of COVID-19 with hyperinflammation and multi-organ involvement was recently recognized, designated the Multisystem Inflammatory Syndrome in Children (MIS-C). Six children with MIS-C with molecular and serologic evidence of SARS-CoV-2 infection were admitted to our hospital between May 5, 2020 and June 25, 2020. All had fever and weakness; 4/6 presented with gastrointestinal symptoms. Two children had features of complete Kawasaki disease, 3 had incomplete Kawasaki disease, while 1 had terminal ileitis with delayed onset of circulatory shock. Treatment consisted of intravenous immunoglobulin and aspirin for Kawasaki-like disease. Remdesivir, corticosteroids, and infliximab were used when indicated. Median hospitalization was 7 days. Immediate treatment resulted in rapid clinical improvement. In children presenting with hyperinflammatory syndromes without cardiac manifestations, testing for SARS-CoV-2 RNA and antibodies, with close cardiac monitoring should be pursued due to the manifold presentations of SARS-CoV-2 infection in children.

Eculizumab-Associated Moraxella lacunata Bacteremia and Systemic Inflammatory Response Syndrome in a Toddler with Atypical Hemolytic Uremic Syndrome.

Moraxella lacunata, a low-virulence Gram-negative coccobacillus, is classically associated with conjunctivitis and upper respiratory tract infections; systemic infections such as sepsis have rarely been reported, especially in children. We describe a 28-month-old girl with atypical hemolytic uremic syndrome and stage II chronic kidney disease on long-term eculizumab therapy who presented with systemic inflammatory response syndrome and was found to have Moraxella lacunata bloodstream infection. Eculizumab, a humanized monoclonal anti-C5 antibody, has been associated with susceptibility to infections with encapsulated bacteria, especially Neisseria meningitidis. This is the first report of an invasive bacterial infection with Moraxella lacunata in a pediatric eculizumab recipient.

Fatal central nervous system co-infection with SARS-CoV-2 and tuberculosis in a healthy child.

BACKGROUND: Central and peripheral nervous system symptoms and complications are being increasingly recognized among individuals with pandemic SARS-CoV-2 infections, but actual detection of the virus or its RNA in the central nervous system has rarely been sought or demonstrated. Severe or fatal illnesses are attributed to SARS-CoV-2, generally without attempting to evaluate for alternative causes or co-pathogens. CASE PRESENTATION: A five-year-old girl with fever and headache was diagnosed with acute SARS-CoV-2-associated meningoencephalitis based on the detection of its RNA on a nasopharyngeal swab, cerebrospinal fluid analysis, and magnetic resonance imaging findings. Serial serologic tests for SARS-CoV-2 IgG and IgA showed seroconversion, consistent with an acute infection. Mental status and brain imaging findings gradually worsened despite antiviral therapy and intravenous dexamethasone. Decompressive suboccipital craniectomy for brain herniation with cerebellar biopsy on day 30 of illness, shortly before death, revealed SARS-CoV-2 RNA in cerebellar tissue using the Centers for Disease Control and Prevention 2019-nCoV Real-Time Reverse Transcriptase-PCR Diagnostic Panel. On histopathology, necrotizing granulomas with numerous acid-fast bacilli were visualized, and Mycobacterium tuberculosis complex DNA was detected by PCR. Ventricular cerebrospinal fluid that day was negative for mycobacterial DNA. Tracheal aspirate samples for mycobacterial DNA and culture from days 22 and 27 of illness were negative by PCR but grew Mycobacterium tuberculosis after 8 weeks, long after the child's passing. She had no known exposures to tuberculosis and no chest radiographic findings to suggest it. All 6 family members had normal chest radiographs and negative interferon-γ release assay results. The source of her tuberculous infection was not identified, and further investigations by the local health department were not possible because of the State of Michigan-mandated lockdown for control of SARS-CoV-2 spread. CONCLUSION: The detection of SARS-CoV-2 RNA in cerebellar tissue and the demonstration of seroconversion in IgG and IgA assays was consistent with acute SARS-CoV-2 infection of the central nervous infection. However, the cause of death was brain herniation from her rapidly progressive central nervous system tuberculosis. SARS-CoV-2 may mask or worsen occult tuberculous infection with severe or fatal consequences.

Life-Threatening Influenza, Hemophagocytic Lymphohistiocytosis and Probable Vaccine-Strain Varicella in a Novel Case of Homozygous STAT2 Deficiency.

STAT2 is a transcription factor that plays an essential role in antiviral immunity by mediating the activity of type I and III interferons (IFN-I and IFN-III). It also has a recently established function in the negative regulation of IFN-I signaling. Homozygous STAT2 deficiency is an ultra-rare inborn error of immunity which provides unique insight into the pathologic consequence of STAT2 dysfunction. We report here a novel genetic cause of homozygous STAT2 deficiency with several notable clinical features. The proband presented aged 12 months with hemophagocytic lymphohistiocytosis (HLH) closely followed by clinical varicella, both occurring within three weeks of measles, mumps, and rubella (MMR) and varicella vaccinations. There was a history of life-threatening influenza A virus (IAV) disease 2 months previously. Genetic investigation uncovered homozygosity for a novel nonsense variant in STAT2 (c. 1999C>T, p. Arg667Ter) that abrogated STAT2 protein expression. Compatible with STAT2 deficiency, dermal fibroblasts from the child demonstrated a defect of interferon-stimulated gene expression and a failure to mount an antiviral state in response to treatment with IFN-I, a phenotype that was rescued by lentiviral complementation by wild type STAT2. This case significantly expands the phenotypic spectrum of STAT2 deficiency. The occurrence of life-threatening influenza, which has not previously been reported in this condition, adds STAT2 to the list of monogenetic causes of this phenotype and underscores the critical importance of IFN-I and IFN-III to influenza immunity. The development of probable vaccine-strain varicella is also a novel occurrence in STAT2 deficiency, implying a role for IFN-I/III immunity in control of attenuated varicella zoster virus in vivo and reinforcing the susceptibility to pathologic effects of live-attenuated viral vaccines in disorders of IFN-I immunity. Finally, the occurrence of HLH in this case reinforces emerging links to hyperinflammation in patients with STAT2 deficiency and other related defects of IFN-I signaling-highlighting an important avenue for further scientific enquiry.

Severe Mitral Regurgitation in a Child With Henoch-Schönlein Purpura and Pulmonary Hemorrhage.

Introduction: Henoch-Schönlein purpura (HSP) is the most common vasculitis of childhood. The classic triad of HSP consists of nonthrombocytopenic purpura, arthritis/arthralgia, and gastrointestinal complaints. Pulmonary hemorrhage and cardiac involvement are rare complications of HSP. Case Report: We report the case of a 10-year-old girl with HSP complicated by both severe mitral regurgitation and pulmonary hemorrhage. Discussion: HSP is typically a self-limited illness with an excellent prognosis in children. Pulmonary hemorrhage is a rare complication that increases morbidity and mortality; it generally indicates the presence of severe vasculitis. Cardiac involvement in HSP is extremely rare and associated with a poor prognosis. Conclusion: Cardiac involvement in HSP may be more common than believed. Because of the increased morbidity and mortality associated with HSP complicated by pulmonary hemorrhage and cardiac involvement, it is important for clinicians to be aware of these potential complications.

Neonatal Pasteurella multocida subsp. septica Meningitis Traced to Household Cats: Molecular Linkage Analysis Using Repetitive-Sequence-Based PCR.

Pasteurella multocida is a rare cause of neonatal bacterial meningitis. We describe such a case and verify two household cats as the source of infection using repetitive-element PCR (rep-PCR) molecular fingering.

Management of neonatal herpes simplex virus infections.

As many as 2,500 infants develop neonatal herpes each year, most of whom are born to women with no history or physical findings suggestive of genital herpes. Infection usually takes one of three forms: 1) disease localized to skin, eyes, and mucous membranes, 2) localized central nervous system infection, or 3) disseminated infection. Exposure to the virus occurs during passage through an infected birth canal, but 5% of infants acquire the infection in utero. The mortality rate is 31% for disseminated infection and 6% for localized central nervous system disease; long-term neurologic sequelae are seen in 17% and 70% of survivors, respectively. Diagnosis is made by isolating of the virus from skin lesions or other involved sites. The polymerase chain reaction for the detection of viral DNA in cerebrospinal fluid or serum is now the diagnostic test of choice for central nervous system or disseminated neonatal herpes because it has higher sensitivity than traditional culture methods. Treatment is with high-dose intravenous acyclovir (60 mg/kg per day in three divided doses), with adjustments made for infants with renal or hepatic insufficiency. Supportive measures and neuroimaging studies are often required. Acyclovir is administered for three weeks, but infants with disease localized to the skin, eyes, and mucous membranes can be treated for two weeks if the cerebrospinal fluid polymerase chain reaction assay is negative for herpes simplex virus DNA. Prevention of infection in infants can be accomplished by cesarean delivery when women have active lesions at the onset of labor. Neonates delivered through an infected birth canal should be screened between 24 and 48 hours of age with viral cultures of eyes, nasopharynx, mouth, and rectum. If positive, they should be treated with acyclovir even if asymptomatic. Suppressive acyclovir therapy beginning at 36 weeks gestation is often prescribed for women with frequent recurrences of genital herpes.