Background: Influenza is a common cause of hospital admissions worldwide, and an increase in influenza cases has been observed following the COVID-19 pandemic. Our study investigated the epidemiological and clinical characteristics of pediatric patients with influenza infection admitted to pediatric intensive care units (PICUs) in Istanbul, Turkey, following the COVID-19 pandemic. Methods: We conducted a retrospective study of pediatric patients with confirmed influenza infection who were admitted to 1 of the 11 PICUs in Istanbul, Turkey, between July 1, 2022, and June 30, 2024. Data on demographic characteristics, risk factors, clinical presentations, microbiological findings, complications and outcomes were systematically collected. Results: A total of 108 children diagnosed with laboratory-confirmed influenza required admission to the PICUs. Sixty-five (60.2%) were diagnosed with influenza A and 43 (39.8%) patients were diagnosed with influenza B. Epidemiologic and clinical characteristics were similar in both influenza types, oxygen saturation was significantly higher in the influenza A group compared to the influenza B group. Severe neurological manifestations, including seizures and encephalitis, were significantly more common in the Influenza A group. In contrast, patients with Influenza B demonstrated a higher incidence of gastrointestinal symptoms, such as nausea, vomiting and abdominal pain. Pneumonia, sepsis and/or multiorgan dysfunction and liver failure were significantly higher in influenza B. Mortality was observed solely in the Influenza B group, with six patients resulting in death, corresponding to a mortality rate of 14%. Conclusions: Influenza virus infection can cause serious multisystem complications such as acute respiratory distress syndrome and encephalitis. Influenza A can present with isolated or predominant neurological manifestations. Mortality may be more common in influenza B.

Introduction: Myocarditis represents a diverse group of inflammatory diseases affecting the heart muscle, with both infectious and non-infectious etiologies. Among the non-infectious causes, drug-induced hypersensitivity reactions are rare but serious. Isoniazid, a cornerstone in tuberculosis treatment, is known for its hepatotoxicity but has rarely been documented to cause hypersensitivity myocarditis.Case report: We present a case of a 15-year-old girl from Eastern Turkmenistan who was admitted to our emergency department with altered consciousness and seizure activity. She was diagnosed with status epilepticus and treated accordingly. The patient, with no prior medical history, was found to have hypotensive shock and myocarditis upon further examination. A detailed history revealed she had ingested 45 tablets of expired isoniazid in a suicide attempt. She was treated with pyridoxine and supportive therapies, resulting in a gradual recovery.Conclusion: This case underscores the critical need to consider drug-induced hypersensitivity myocarditis in the differential diagnosis of myocarditis, especially in patients with recent medication use. Prompt recognition and appropriate treatment with pyridoxine, steroid, and supportive cardiac care can be lifesaving. This case also highlights the importance of awareness regarding the potential cardiotoxic effects of isoniazid overdose.

Introduction: Hyperammonemia occurs as a result of the inability to convert ammonia, a metabolic toxin, into urea due to a block in the urea cycle, and there resulting neurotoxicity is responsible for the pathogenesis. Case Presentation: Our patient was 7 days old when followed up in an external center for 3 days with a preliminary diagnosis of neonatal sepsis. Lethargy, vomiting, tachypnea, and convulsions, which are frequently seen in the first neonatal forms of urea cycle disorders, were also present in our patient. He was referred to us as a result of high ammonia levels when he was examined in terms of congenital metabolic diseases. He was intubated due to the rapid development of respiratory failure. When he was admitted to our intensive care unit with hyperammonemia, light reflex could not be obtained, and widespread cutis marmaratus was developed. Continuous renal replacement therapy was started in our patient and administered intermittently for 120 hours. The glucose infusion rate was followed by high fluid. When it orally tolerated, it is supported with sodium benzoate and sodium stearyl fumarate to reduce ammonia. Nutrition was limited to protein with Basic P. Conclusion: After staying in the intensive care unit for 30 days, our patient was discharged with the recommendation of outpatient follow-up by the pediatric metabolism physician. When our patient came for his check up after two months, there was no nystagmus and no seizures.