COVID-19-associated transverse myelitis treated by therapeutic plasma exchange: A case report.

BACKGROUND: Transverse myelitis (TM) is a very uncommon condition in children which can be associated with viral infections. Acute TM cases have been reported after Coronavirus disease 2019 (COVID-19) infection during the pandemic. CASE REPORT: We report a child with TM related to severe acute respiratory syndrome coronavirus 2, who was successfully treated with therapeutic plasma exchange (TPE). Inability to walk and urinary retention were the central nervous system symptom. Spinal magnetic resonance imaging revealed signal changes in the spinal cord. Her neurological symptoms worsened despite receiving IVIG and high-dose steroids for the first 3 d. We performed 10 TPE sessions with 5% albumin replacement and the neurological symptoms rapidly improved. CONCLUSION: We demonstrated that a child diagnosed with acute TM related to COVID-19 infection, was successfully treated with TPE.

Volumetric apparent diffusion coefficient (ADC) histogram analysis of the brain in paediatric patients with hypoxic ischaemic encephalopathy.

Purpose: To evaluate the whole brain, hippocampus, thalamus, and lentiform nucleus by volumetric apparent diffusion coefficient (ADC) histogram analysis in paediatric patients with hypoxic-ischaemic encephalopathy (HIE). Material and methods: This retrospective study included 25 patients with HIE and 50 patients as the control group. Diffusion-weighted imaging was obtained at b-values of 1000 mm2/s. The histogram parameters of ADC values, including the mean, minimum, maximum, 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles, as well as skewness, kurtosis, and variance were determined. The interclass correlation coefficient (ICC) was used to assess the inter-observer agreement. Results: ADCmin, ADCmean, and ADCmax, as well as the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles of ADC values for the HIE group were all lower than those of the control group (p < 0.001) in the volumetric histogram analysis of the hippocampus, thalamus, and lentiform nucleus. In the whole-brain histogram analysis, ADC min, and the 50th and 75th percentiles of ADC values did not differ significantly, while other parameters were lower in the HIE group. The ROC curve revealed that the ADC histogram parameters of the hippocampus provided the most accurate results for the diagnosis of HIE. The area under the curve (AUC) of the 95th percentile of ADC values was the highest (AUC = 0.915; cut-off 1.262 × 10-3 mm2/s; sensitivity 88% and specificity 84%). Conclusions: Volumetric ADC histogram analysis of the whole brain, hippocampus, thalamus, and lentiform nucleus with b-values of 1000 mm2/s can serve as an imaging marker for determining HIE.

Use of Bedside Ultrasonography and Saline Flush Technique for Evaluation of Central Venous Catheter Placement in Children.

Our study investigated the reliability of appearance of rapid atrial swirl flow (RASF) by ultrasonography (US) in the right atrium (RA), which occurred as a result of rapid isotonic saline infusion (RISI) into the central venous catheter (CVC), in predicting catheter tip position. This prospective observational study included 95 CVC procedures performed on 77 pediatric patients (41 boys and 36 girls) with a median age of 0.6 (0.29-1.53) years. Seventy-three (76.84%) catheter tips were found to be correctly placed, and 22 (23.15%) catheter tips were misplaced. While ultrasonographic examination revealed RASF in the RA after 93 catheterization procedures, it was not observed after two catheterization procedures. One of these two catheters was an arterial catheter, and the other was a catheter that was directed toward the subclavian vein after curling around itself. There was no significant difference between the groups with incorrect and correct positioned catheter tip in terms of the appearance of RASF by US after RISI. There was no significant difference between the groups with upward (n = 8) and downward (n = 86) positioned catheter tip in terms of the time until the first appearance of RASF after RISI and the phase of RASF (P > 0.05). There was a significant difference between these two groups in terms of the disappearance time of RASF in the RA (P < 0.001). The mean disappearance time of RASF was 3 (2-3) s for downward positioned catheters and 5 (4-7) s for upward positioned catheters, respectively. When the cut-off for the disappearance time of RASF was set to 3 s, US had a sensitivity of 85.71% and a specificity of 77.91% for detecting upward positioned catheters. In conclusion, the appearance of RASF in the RA in a short time by US is not a reliable finding for correct positioning of the CVC tip in the pediatric patient group. The fact that the disappearance time of RASF in the RA is longer than 3 s indicates upward positioned CVCs. These catheters must never be used without radiological confirmation. In CVCs in which the disappearance time of RASF in the RA is shorter than 3 s, we think that the catheter can be used until radiological confirmation in emergency cases. According to the available literature, our study is the first study in children. There is a need for new studies on this subject.

Evaluation of Liver, Kidney, and Spleen Elasticity in Healthy Newborns and Infants Using Shear Wave Elastography.

OBJECTIVES: Elasticity measurements of tissues can be valuable in the diagnosis and management of various diseases. The aim of this study was to determine the elasticity values for normal liver, kidney, and spleen of healthy newborns and infants using shear wave elastography (SWE) imaging. METHODS: A total of 50 healthy term newborns and infants (19 girls and 31 boys; mean age 20.1 days, range 1 to 70 days) were examined by an experienced pediatric radiologist using SWE. None of them had any liver, kidney or spleen disease, or any other systemic disease that could affect these organs secondarily. All newborns and infants had a normal abdominal ultrasound scan. RESULTS: Age, sex, weight, height, and body mass index had no significant effects on shear wave velocity (SWV) values of liver and spleen. The SWV values of both kidneys decreased with age, weight, height, and body mass index. The mean SWV values were 1.70 m/s (range: 1.23-2.43 m/s) for the liver, 1.69 m/s (range: 0.8-2.40 m/s) for the right kidney, 1.70 m/s (range: 0.9-2.49 m/s) for the left kidney, and 2.03 m/s (range: 1.28-2.48 m/s) for the spleen. CONCLUSIONS: Shear wave elastography can be used to measure liver, kidney, and spleen elasticity in newborns and infants. The standard values for abdominal organs allow differentiation of healthy versus pathological tissue. We measured the normal values of SWE in healthy newborns and infants as reference data.

Leptomeningeal dissemination and vertebral bone involvement in a child with pilocytic astrocytoma.

In low-grade glioma, metastasis is rarely seen. Few cases of leptomeningeal dissemination have been reported in children. Vertebral bone metastasis has not been reported so far. Herein is described the case of a pediatric patient with the diagnosis of pilocytic astrocytoma, and leptomeningeal dissemination detected at the time of diagnosis, who then received radiotherapy and chemotherapy upon development of vertebral bone metastasis during treatment.

Temporal High-Resolution Computed Tomography and Magnetic Resonance Imaging of Congenital Inner Ear Anomalies in Children.

Imaging plays an important role in determining indications of cochlear implantation and choosing candidates for the procedure in children. Temporal high-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) can display precisely the complex anatomic structure of inner ear. Although HRCT permits detailed imaging of bony structures, MRI gives valuable information about membranous labyrinth, internal acoustic canal, and vestibulocochlear nerve. Magnetic resonance imaging examination of the brain should be performed at the same time to evaluate any coexistent brain parenchymal abnormality. These imaging modalities are complementary methods in evaluating congenital inner ear anomalies. The aim of this pictorial essay is to reviewing temporal HRCT and MRI findings of congenital inner ear anomalies.

Pott Puffy Tumor in Children: A Rare Emergency Clinical Entity.

OBJECTIVES: Pott puffy tumor (PPT) is defined as soft tissue swelling of the forehead due to subperiosteal edema, accumulation of pus, or granulation tissue. It is associated with osteomyelitis of frontal bone secondary to frontal sinusitis. Pott puffy tumor can be complicated by preseptal and orbital cellulitis and intracranial infection. METHODS: Six patients diagnosed with and treated for PPT in Pediatric Clinic of Uludag University Faculty of Medicine from 2010 to 2015 were reviewed retrospectively. Age, sex, presenting symptoms and signs, laboratory and radiological findings, as well as intracranial complications and treatment modalities of all patients were evaluated. RESULTS: The authors present 6 pediatric patients of PPT, 5 males and 1 female with a mean age of 11 years (age range, 7-18 years). All patients presented with headache, fever, and tender frontal swelling. Two of the patients had epidural abscess and 1 had preseptal orbital cellulitis in addition to PPT. All of them had computed tomography scan and/or magnetic resonance imaging. Endoscopic sinus surgery was performed in 4 patients and 2 patients underwent neurosurgical intervention with antibiotherapy. CONCLUSIONS: Pott puffy tumor may be associated with potentially dangerous intracranial complications. Early diagnosis and treatment are essential to reduce morbidity and mortality. Imaging plays an important role in the diagnosis of the disease and the detection of its complications.

[A case of bronchiolitis obliterans secondary to human metapneumovirus bronchiolitis]. / Insan metapnömovirus bronsiyolitine ikincil gelisen bronsiyolitis obliterans olgusu.

Human metapneumovirus (hMPV), formerly classified in Paramyxoviridae family is now moved into Pneumoviridae, which was described as a novel family. It causes upper and lower respiratory tract infections (LRTIs) usually in children younger than five years old. The recent epidemiological studies indicated that hMPV is the second most frequently detected virus in LRTIs of young children, following the respiratory syncytial virus (RSV). Bronchiolitis obliterans (BO) is a chronic obstructive lung disease characterized by fibrosis of the distal respiratory airways. It is usually a result of an inflammatory process triggered by a LRTI related to adenovirus, RSV, Mycoplasma pneumoniae, measles virus, Legionella pneumophila, influenza virus or Bordetella pertussis as a causative agent. In this report, a case of hMPV bronchiolitis complicated with BO has been reported to point out the complications and severity of the clinical progress belongs to this virus. A three-month-old female patient has admitted to our pediatric intensive care unit with the diagnosis of acute bronchiolitis and respiratory failure. She was born at term, weighing 2950 gram and had been hospitalized in newborn intensive care unit for 11 days with the diagnosis of transient tachypnea of the newborn and neonatal sepsis. On auscultation, there were bilateral crepitant rales, wheezing and prolonged expirium. Her oxygen saturation was 97-98% while respiratory support was given with a non-rebreathing reservoir mask. Complete blood count, procalcitonin and C-reactive protein levels were in normal ranges. The chest radiography yielded right middle lobe atalectasia, left paracardiac infiltration and bilateral air trapping. A nasopharyngeal swab sample was analyzed by a commercial multiplex real-time reverse transcriptase-polymerase chain reaction (Thermo Fisher Scientific®, USA) developed for the detection of 15 respiratory viruses. Her sample yielded positive result for only hMPV. On the 4th day of hospitalization, the patient was intubated because of respiratory failure and carbon dioxide retention. She was extubated on the 19th day but could not tolerate. In the thorax computed tomography (CT), bilateral hyperinflation, patchy infiltration, mosaic perfusion and atelectasis especially bilateral posterior areas were detected. Bronchoscopy was normal except mild bronchomalacia in right middle lobe bronchus. The patient was diagnosed as BO secondary to hMPV bronchiolitis, according to the clinical, virological, bronchoscopic and thorax CT results. On the 76th day of admission, she was discharged with respiratory support with home ventilation via a tracheostomy cannula and medical treatments of oral metilprednisolone, nebulized salbutamol and budesonide. In conclusion, hMPV should not be undervalued especially in infants with severe LRTI that can be complicated with BO.

Evaluation of Cerebrovascular Events Followed in Pediatric Intensive Care Unit.

AIM: To evaluate the effect of intensive care follow-up and treatment methods on the prognosis of 28 patients admitted to the pediatric intensive care unit (PICU) due to stroke. MATERIAL AND METHODS: The data of patients aged between 28 days and 18 years followed up between 2011 and 2021 were recorded retrospectively. RESULTS: Thirteen (48.1%) patients were diagnosed with hemorrhagic stroke (HS), 11 (40.7%) patients were diagnosed with acute ischemic stroke (AIS), and three (11.1%) patients were diagnosed with cerebral sinus vein thrombosis. One patient was followed up for non-ruptured arteriovenous malformation (AVM) and was excluded from the HS group. The HS group consisted of eight patients with ruptured AVMs and five patients with ruptured intracranial aneurysms. The patients had male predominance, and seizures and headache were the most common complaints on admission. The rate of admissions due to seizures was higher in the AIS group. In the HS group, there was more involvement of the right side of the brain. Middle cerebral artery (MCA) involvement was higher in the AIS group. The AIS group had longer PICU hospitalization days and mechanical ventilator days. While unfractionated heparin was preferred for the treatment in the AIS group, endovascular embolization was preferred in the HS group. Decompressive surgery was performed in five patients. The overall mortality rate was 7.1%. CONCLUSION: Although cerebrovascular events are rare in the pediatric population, achieving low mortality and morbidity is possible with the correct diagnostic and treatment methods.

Use of sonography for evaluation of the cervical and thoracic esophagus in children.

OBJECTIVES: The purpose of this study was to determine the normal sonographic appearance of the cervical and thoracic esophagus and to provide corresponding measurements in healthy children. METHODS: In this prospective study, 93 children (51 girls and 42 boys) 1 to 15 years of age were examined sonographically. With the patient in a supine position for evaluation of the cervical esophagus, the ultrasound transducer was placed on both sides of the trachea. To evaluate the thoracic esophagus, the hands were raised over the head, and the ultrasound transducer was placed along the left side of the sternum. The length of the cervical esophagus was measured longitudinally, and the anteroposterior and transverse diameters of the cervical and thoracic esophagus were measured transversely, as was the thickness of the cervical esophageal wall. RESULTS: The cervical esophagus was identified in all of the children, whereas the thoracic esophagus was shown in 41 (44%) of the 93 participants. The length of the cervical esophagus and anteroposterior and transverse diameters of the cervical and thoracic esophagus increased with age. The mean thickness of the cervical esophagus was 2.8 mm at all ages. The cervical esophageal wall appeared as 5 layers on the sonograms, and the lumen was distinct. CONCLUSIONS: Evaluation of the cervical esophagus was readily achievable with sonography in children, whereas visualization of the thoracic esophagus was difficult because of the deep location, small size, and influence of bones and gas in the lungs. Conventional sonography can be easily used in the evaluation of cervical esophageal diseases in children.

Bilateral lentiform and caudate nucleus lesions in a child with COVID-19: A case report.

Neurological complications are frequently mentioned in the published reports regarding the coronavirus disease 2019 (COVID-19). Especially encephalopathy draws attention as the leading symptom or complication of COVID-19 in some reports. This article discussed a 3-year-old patient with bilateral lentiform and caudate nuclei involvement on brain imaging, who presented with mental status changes and acute muscular weakness, possibly due to COVID-19. To the best of our knowledge, this case is the first one showing pathological signal enhancement and edema in bilateral lentiform and caudate nuclei associated with COVID-19.

Acute Cerebellitis in MIS-C: A Case Report.

BACKGROUND: Coronavirus disease-2019 (COVID-19) is characterized predominantly by respiratory symptoms and has affected a small subset of children. Multisystem inflammatory syndrome in children (MIS-C) has been reported in children following COVID-19. There is increasing report that COVID-19 may also lead to neurologic manifestations. Cerebellar lesions may be observed in viral infections. CASE REPORT: We report a child with MIS-C related to severe acute respiratory syndrome coronavirus 2, who developed cerebellar lesion during the disease course. Encephalopathy was the first central nervous system symptom. His consciousness improved but he developed clinical signs of cerebellar dysfunction including ataxia, dysarthria and nystagmus. Brain magnetic resonance imaging (MRI) revealed symmetrical pathological signal changes in both cerebellar hemispheres. CONCLUSION: We demonstrated the first child with MIS-C to develop cerebellar lesion on brain MRI, suggestive of cerebellitis.

Evaluation of the impact of childhood obesity on retrobulbar hemodynamics and retinal microvasculature.

OBJECTIVE: To evaluate changes in retrobulbar ocular blood flow parameters by using Colour Doppler Imaging (CDI) and changes in foveal microvasculature by using Optical Coherence Tomography Angiography (OCTA) in pediatric obese patients and to compare them with a group of healthy children. METHODS: Children diagnosed with obesity without hypertension and diabetes (39 subjects, obese group) and age-matched healthy controls (26 subjects, control group) underwent CDI and OCTA imaging. Peak systolic velocity, end-diastolic velocity and resistivity index from ophthalmic, central retinal and posterior ciliary arteries on CDI; superficial and deep capillary plexus vascular density and foveal avascular zone area on OCTA imaging were obtained in each group. Central foveal and subfoveal choroidal thicknesses were also measured. CDI and OCTA parameters were compared between two groups. RESULTS: Peak systolic and end-diastolic velocities were found to be significantly lower in obese children than in controls in all three examined arteries (p < 0.05). Resistivity index values were similar between the groups. OCTA imaging did not reveal significant changes in superficial and deep capillary plexus vascular densities and foveal avascular zone area across analysed retinal regions between the groups. Subfoveal choroid was thicker in obese group than in control group (325.89 ± 52.77 µm vs. 304.52 ± 21.76 µm, p = 0.04). CONCLUSION: An apparent decrease was present in retrobulbar hemodynamics in obese children. This arises the possibility of early ocular macrovascular compromise rather than retinal microvascular impairment in childhood obesity.

Preseptal and Orbital Cellulitis: Analysis of Clinical, Laboratory and Imaging Findings of 123 Pediatric Cases From Turkey.

BACKGROUND: We aimed to compare the clinical and laboratory characteristics and imaging methods of patients diagnosed with preseptal cellulitis and orbital cellulitis in the pediatric age group. METHODS: The study was designed retrospectively, and the medical records of all patients who were hospitalized with the diagnosis of preseptal cellulitis and orbital cellulitis were reviewed. The findings of preseptal cellulitis and orbital cellulitis groups were compared. The risk factors for the development of orbital involvement were analyzed. RESULTS: A total of 123 patients were included, 90.2% with preseptal cellulitis and 9.8% with cellulitis. The male gender ratio was 60.2%, and the mean age was 72 ± 43 months. While all patients had eyelid swelling and redness, 20.3% had fever. Ocular involvement was 51.2% in the right eye and 4.9% in both eyes. The most common predisposing factor was rhinosinusitis (56.1%). Radiologic imaging (computed tomography/magnetic resonance imaging) was performed in 83.7% of the patients. Subperiostal abscess was detected in 7 cases (5.6%) in which three of the cases were managed surgically and four were treated with medically. The levels of C-reactive protein were significantly higher in patients with orbital involvement (P = 0.033), but there was no difference between the presence of fever, leukocyte and platelet values. CONCLUSIONS: Rhinosinusitis was the most common predisposing factor in the development of preseptal cellulitis and orbital cellulitis. Orbital involvement was present in 9.8% of the patients. It was determined that high C-reactive protein value could be used to predict orbital involvement.

Imaging of Multisystem Inflammatory Disease in Children (MIS-C) Associated With COVID-19.

RATIONALE AND OBJECTIVES: To retrospectively evaluate imaging findings in multisystem inflammatory disease in children associated with COVID-19 (MIS-C). MATERIALS AND METHODS: The radiological imaging findings of 45 pediatric patients aged between 52 days and 16 years, who were diagnosed with MIS-C according to the World Health Organization (WHO) criteria, were evaluated. All the patients underwent chest X-ray and echocardiography. The findings obtained from 25 abdominal radiographs, 24 abdominal US, 7 abdominal CT, 16 thorax CT, 21 cranial MRI and one spinal MRI, MR cholangiography (MRCP) and cardiac MRI examinations were categorized and evaluated according to the affected systems. RESULTS: While the most common findings in chest X-ray were perihilar opacity and peribronchial thickening, pleural effusion was the most finding in thorax CT. Echocardiography findings of myocarditis were observed in 31% of the cases. The most common findings in abdominal radiological evaluation were hepatomegaly and splenomegaly, edema in the gallbladder wall and periportal area, mesenteric lymph nodes in the right lower quadrant, thickening of the intestinal walls, and free fluid. Reversible splenial lesion syndrome (RESLES) was the most common neurological finding. Acute disseminated encephalomyelitis (ADEM)-like lesions, acute hemorrhagic necrotizing encephalomyelitis, and radiological findings consistent with Guillain-Barré syndrome were found in one case each. CONCLUSION: Radiological findings seen in MIS-C in pediatric cases are correlated with the affected system. According to the system involved, there is no specific finding for this disease. Radiological findings are not the primary diagnostic tool but can assist in the evaluation of the affected systems and to guide treatment.

The performance of shear wave elastography on evaluating liver changes in obese and overweight children.

BACKGROUND: Real time shear-wave elastography (SWE) is a non-invasive imaging method which can quantitatively assess liver stiffness. Obesity and its complication are increasing with improving lifestyles in our century. We evaluated the performance of SWE for detecting liver changes (fatty liver, steatohepatitis) in obese and overweight children, in addition to this, we determined the diagnostic accuracy and clinical usefulness of SWE in non-alcoholic fatty liver disease (NAFLD). METHODS: Obese and overweight 41 children within the age range of 6-15 years were included in this singlecenter prospective study. Biochemical evaluation for aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglyceride (TG), total cholesterol (TC) levels, as well as conventional ultrasound and SWE of the liver were performed in the patient group. These values were compared with values of 25 normal weight and healthy children in the age range of 6-16 years. RESULTS: The mean SWE values was 13.7 ± 5.5 kiloPascal (kPa) and 2.03 ± 0.35 meter/second (m/s) in patient group and 7.99 ± 2.81 kPa and 1.62 ± 0.21 m/s in control group (p < 0.01). The receiver-operating characteristics (ROC) analysis was performed to determine the optimum cut-off value for elastography values (kPa) to evaluate liver changes; area under the curve was 87.5% (95% CI 79.3-95.8). When the cutoff value was set as 10.45 kPa, the sensitivity and the specificity was 69.2% and 100%, respectively. We could not observe a statistically significant difference when we compared the elastography values (kPa and m/s) according to presence of hepatosteatosis (p=0.581 and 0.172). There were no significant correlations between SWE and AST, ALT values. CONCLUSIONS: SWE may be a useful and accurate imaging method to evaluate liver changes and monitor NAFLD in obese and overweight children.

COVID-19-associated Acute Disseminated Encephalomyelitis-like Disease in 2 Children.

BACKGROUND: The coronavirus disease 2019 pandemic was caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although the predominant clinical presentation is a respiratory disease, neurologic manifestations are being recognized increasingly. CASE REPORT: We report 2 children 9 years of age who developed acute disseminated encephalomyelitis-like disease associated with SARS-CoV-2. Seizures and encephalopathy were the main central nervous system symptoms. The cerebrospinal fluid analysis performed within the first week of disease onset showed elevated protein in both children with normal cell count and no evidence of infection including negative SARS-CoV-2 by antibody and polymerase chain reaction. Brain magnetic resonance imaging revealed T2A, fluid-attenuated inversion recovery cortical and subcortical hyperintensity without restricted diffusion consistent with acute disseminated encephalomyelitis-like disease. They received methylprednisolone followed by therapeutic plasma exchange. One of them showed complete clinical improvement and resolution in magnetic resonance imaging findings. The other developed laminar necrosis in brain magnetic resonance imaging and showed significant clinical improvement after therapeutic plasma exchange. He was positive for positive SARS-CoV-2 antibody in cerebrospinal fluid on day 55 of admission. They were both positive for SARS-CoV-2 antibodies in serum after 2 weeks. CONCLUSIONS: Our two cases highlight the occurrence of acute disseminated encephalomyelitis-like disease as a postinfectious/immune-mediated complication of SARS-CoV-2 infection.

Cytotoxic lesions of the corpus callosum in children: Etiology, clinical and radiological features, and prognosis.

OBJECTIVES: Cytotoxic lesions of the corpus callosum (CLOCCs) are secondary lesions associated with entities like infection manifested by restricted diffusion on diffusion-weighted cranial magnetic resonance imaging. Our objectives are to evaluate the clinic-radiological spectrum of pediatric patients with cytotoxic lesions of the corpus callosum (CC). METHODS: Children (0-18 years) admitted between February 2017 and May 2020 with splenial lesions showing diffusion restriction on MRI, either isolated or within involvement of other parts of the brain, were included retrospectively. The primary lesions of the CC (e.g. acute disseminated encephalomyelitis, acute ischemic infarction, and glioblastoma multiforme) were excluded. CLOCCs were divided into infection-associated, metabolic disorder-associated, and trauma-associated lesions, as well as CLOCCs involving other entities. Data were collected from the medical databases. RESULTS: Forty-one patients were determined to have CLOCCs. Twenty-five (61%) were infection-associated, nine (22%) were trauma-associated, and three (7%) were metabolic disorder-associated cases, including 2 inherited disorders of metabolism. There were four (10%) patients with other entities, three with epilepsy, and one had an apparent life-threatening event. Six patients had a known etiology among the infection-associated group; one had multisystem inflammatory syndrome caused by COVID-19 and one had been infected by COVID-19 without any complications. All the infection-associated patients with isolated splenial lesions recovered totally, although six patients required intensive care hospitalization. Four trauma-associated patients had sequela lesions. CONCLUSIONS: CLOCCs are associated with a spectrum of diseases, including the new coronavirus, COVID-19 infection. Infection-associated CLOCCs has the best prognosis, although severe cases may occur. Sequelae are possible based on the etiology.

X-linked recessive TLR7 deficiency in ~1% of men under 60 years old with life-threatening COVID-19.

Autosomal inborn errors of type I IFN immunity and autoantibodies against these cytokines underlie at least 10% of critical COVID-19 pneumonia cases. We report very rare, biochemically deleterious X-linked TLR7 variants in 16 unrelated male individuals aged 7 to 71 years (mean: 36.7 years) from a cohort of 1,202 male patients aged 0.5 to 99 years (mean: 52.9 years) with unexplained critical COVID-19 pneumonia. None of the 331 asymptomatically or mildly infected male individuals aged 1.3 to 102 years (mean: 38.7 years) tested carry such TLR7 variants (p = 3.5 × 10-5). The phenotypes of five hemizygous relatives of index cases infected with SARS-CoV-2 include asymptomatic or mild infection (n=2, 5 and 38 years), or moderate (n=1, 5 years), severe (n=1, 27 years), or critical (n=1, 29 years) pneumonia. Two boys (aged 7 and 12 years) from a cohort of 262 male patients with severe COVID-19 pneumonia (mean: 51.0 years) are hemizygous for a deleterious TLR7 variant. The cumulative allele frequency for deleterious TLR7 variants in the male general population is < 6.5x10-4 We also show that blood B cell lines and myeloid cell subsets from the patients do not respond to TLR7 stimulation, a phenotype rescued by wild-type TLR7 The patients' blood plasmacytoid dendritic cells (pDCs) produce low levels of type I IFNs in response to SARS-CoV-2. Overall, X-linked recessive TLR7 deficiency is a highly penetrant genetic etiology of critical COVID-19 pneumonia, in about 1.8% of male patients below the age of 60 years. Human TLR7 and pDCs are essential for protective type I IFN immunity against SARS-CoV-2 in the respiratory tract.

Imaging of COVID-19 pneumonia in children.

OBJECTIVE: Literature related to the imaging of COVID-19 pneumonia, its findings and contribution to diagnosis and its differences from adults are limited in pediatric patients. The aim of this study was to evaluate chest X-ray and chest CT findings in children with COVID-19 pneumonia. METHODS: Chest X-ray findings of 59 pediatric patients and chest CT findings of 22 patients with a confirmed diagnosis of COVID-19 pneumonia were evaluated retrospectively. RESULTS: COVID-19 pneumonia was most commonly observed unilaterally and in lower zones of lungs in chest X-ray examinations. Bilateral and multifocal involvement (55%) was the most observed involvement in the CT examinations, as well as, single lesion and single lobe (27%) involvement were also detected. Pure ground-glass appearance was observed in 41%, ground-glass appearance and consolidation together was in 36%. While peripheral and central co-distribution of the lesions (55%) were frequently observed, the involvement of the lower lobes (69%) was significant. In four cases,the coexistence of multiple rounded multifocal ground-glass appearance and rounded consolidation were observed. CONCLUSION: COVID-19 pneumonia imaging findings may differ in the pediatric population from adults. In diagnosis, chest X-ray should be preferred, CT should be requested if there is a pathologic finding on radiography that merits further evaluation and if clinically indicated. ADVANCES IN KNOWLEDGE: Radiological findings of COVID-19 observed in children may differ from adults. Chest X-ray should often be sufficient in children avoiding additional irradiation, chest CT needs only be done in cases of clinical necessity.