A pediatric case of Takayasu's arteritis with anti-neutrophil cytoplasmic antibody-associated vasculitis triggered by COVID-19 infection.

Takayasu's arteritis (TA) is a rare chronic granulomatous vasculitis characterized by large-vessel involvement. The aorta and its main branches are most commonly involved. Although pulmonary artery involvement is common, hemoptysis or respiratory findings are rarely seen. Herein, we present a case of TA who developed anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis with diffuse alveolar hemorrhage after coronavirus disease 2019 (COVID-19) infection. A 17-year-old female patient with the diagnosis of TA presented with cough, bloody vomiting, and diarrhea. In follow-up, she developed tachypnea and dyspnea and was transferred to the pediatric intensive care unit. The findings on the chest computed tomography were compatible with acute COVID-19 infection, but the SARS-CoV2 reverse transcription-polymerase chain reaction test was negative, but SARS-CoV2 immunoglobulin (Ig) G and IgM antibody tests were positive. The patient was not vaccinated against COVID-19. The bronchoscopy showed bronchial mucosal fragility, bleeding foci, and mucosal bleeding. The broncoalveolar lavage hemosiderin-laden macrophages were seen in the histopathologic examination. The indirect immunofluorescence assay-ANCA test became 3 (+) with myeloperoxidase (MPO)-ANCA of 125 RU/ml (normal: <20). Cyclophosphamide and pulse steroid treatment were started. After immunosuppressive therapy, the patient condition improved and did not have hemoptysis again. The successful response was obtained by applying balloon angioplasty to the patient with bilateral renal artery stenosis. Types of post-COVID vasculitis include thromboembolic events, cutaneous vasculitis, Kawasaki-like vasculitis, myopericarditis, and ANCA-associated vasculitis. It is thought that COVID-19 may impair immune tolerance and trigger autoimmunity with cross-reaction. To the best of our knowledge, the third pediatric case was reported with MPO-ANCA-positive COVID-associated ANCA vasculitis.

Anaphylaxis during puncture of a hepatic hydatid cyst.

Although hydatid cyst infects many organs, it most commonly involves liver, lungs, and central nervous system. The goal of hydatid cyst treatment is to completely eliminate the parasite and to prevent recurrences with minimal mortality and morbidity. The procedure of puncture, aspiration, injection of a scolicidal, and reaspiration (PAIR) of a cyst has been introduced as an alternative to surgical method since it is less invasive and less morbid and is associated with a shorter hospital stay and a lower cost. Herein, we report an 11-year-old girl who developed anaphylaxis during the puncture of a hepatic hydatid cyst. The patient who developed anaphylaxis during the PAIR procedure was administered intravenous adrenaline, methyl prednisolone, and antihistaminic medication. She was intubated and provided assisted ventilation using a mechanic ventilator. The child was extubated 4 h after her admission to the pediatric intensive care unit. During follow-up, the contents of her hepatic hydatid cysts were aspirated through a catheter, followed by their irrigation with 20% sodium chloride and re-aspiration. Then, 97% ethyl alcohol was injected into the cyst cavity to make it collapse. The goal of this report was to draw attention to the rare occurrence of anaphylaxis during the PAIR procedure and to stress that clini-cians should be vigilant for this complication.

Hashimoto Encephalopathy.

Hashimoto encephalopathy (HE) is a steroid-responsive, acute or subacute encephalopathy, characterised by autoimmune thyroiditis associated with elevated antithyroid antibody titres. An 11-year-old girl was admitted to the Department of Paediatrics with generalised tonic-clonic seizures, left facial paralysis and right hemiparesis. Ceftriaxone and acyclovir were applied, and methyl prednisolone 2 mg kg-1 day-1 was administered orally. The hemiparesis improved on the 3rd day of treatment, but the facial paralysis persisted into the 15th day. When she developed somnolence, she was transferred to the paediatric intensive care unit and provided with respiratory support after intubation. Antithyroid peroxidase (Anti-TPO) and Antithyroglobulin antibody (Anti-Tg) levels were measured at 112.3 IU mL-1 and 74.6 IU mL-1, respectively. HE was considered as the provisional diagnosis, for which intravenous methyl prednisolone 30 mg kg-1 for 5 days followed by prednisolone 1.5 mg kg-1 day-1 were administered. The patient's clinical status did not improve; therefore, she underwent therapeutic plasma exchange (1/1 ratio) for 8 days, followed by intravenous immunoglobulin 1 gr kg-1 for 2 days. As her clinical condition did not improve, rituximab and endoxane treatments were planned. Unfortunately, these treatments were postponed as she developed ventilator-associated pneumonia at the follow-up. She developed septic shock on the 14th day of follow-up, and noradrenaline and dopamine infusions were commenced. Despite all the efforts, she remained unresponsive and died from cardiac arrest. By reporting this case, we aimed to stress that HE should be considered as an aetiology of encephalopathy when infectious, neoplastic, autoimmune, toxic and metabolic causes are excluded.

Hypophosphatemia associated risk factors in pediatric intensive care patients.

San ES, Erdogan S, Bosnak M, San M. Hypophosphatemia associated risk factors in pediatric intensive care patients. Turk J Pediatr 2017; 59: 35-41. The aim of this work is to determine the prevalence and risk factors of hypophosphatemia in pediatric patients admitted to intensive care unit. The study was performed prospectively in patients admitted to the Pediatric Intensive Care Unit between June 2014 and December 2014. Fifty-seven patients were included in the study. The mean age of the study population was 24 months (2-192 months); 25 patients (43.9%) were male and 32 were female (56.1%). The mean body weight z-score was -1.47 ± 2.23, and 23 (40.4%) patients had malnutrition. On admission 16 (28.1%) patients had hypophosphatemia. There were no statistically significant differences between the hypophosphatemic patient group and normophosphatemic patient groups in terms of demographic and clinical characteristics. There were also no significant differences between the two groups in terms of risk factors. Potassium and creatinine levels were significantly lower in the hypophosphatemic group, compared to the normophosphatemic group. According to a multivariate logistic regression analysis, risk factors for hypophosphatemia were low potassium level (OR: 16.76; 95% CI: 2.09 - 134.72; p: 0.008), malignant solid tumors (OR: 52.40; 95% CI: 2.04 - 1,344.32; p: 0.017, p: 0.036). and female gender (OR: 6.18; 95% CI: 1.12 - 34.00; p: 0.036). Prospective studies with larger sample size should be conducted to study the prevalence and risk factors of hypophosphatemia at pediatric intensive care unit.

Therapeutic plasma exchange in primary hemophagocytic lymphohistiocytosis: Reports of two cases and a review of the literature.

We report two children who were diagnosed as having primary hemophagocytic syndrome and who successfully underwent therapeutic plasma exchange (TPE). The first patient was a 6-month-old girl diagnosed with HLH who was admitted to the pediatric intensive care unit. The patient's clinical condition worsened on the 9th day of the HLH-2004 treatment protocol. Her ferritin level was found 50.000 ng/mL, and TPE was performed for 9 sessions, after which her clinical condition and laboratory findings improved. The patient is still on the HLH-2004 protocol and waits for a suitable stem cell transplantation donor. Case 2 involved a Syrian girl with HLH under follow-up who was receiving the HLH-2004 treatment protocol for reactivation. She presented to emergency department with fever, where her ferritin level was measured greater than 100.000 ng/mL; she was then transferred to the pediatric intensive care unit where four sessions of TPE were performed, after which her clinical condition and laboratory findings improved. However, the patient was admitted again one month later with gastrointestinal bleeding and died despite all efforts. By describing these two cases, we wish to emphasize that TPE can produce a rapid improvement until the time of stem cell transplantation in patients with hemophagocytic syndrome who do not respond to traditional treatments.