Human IRF1 governs macrophagic IFN-γ immunity to mycobacteria.

Inborn errors of human IFN-γ-dependent macrophagic immunity underlie mycobacterial diseases, whereas inborn errors of IFN-α/ß-dependent intrinsic immunity underlie viral diseases. Both types of IFNs induce the transcription factor IRF1. We describe unrelated children with inherited complete IRF1 deficiency and early-onset, multiple, life-threatening diseases caused by weakly virulent mycobacteria and related intramacrophagic pathogens. These children have no history of severe viral disease, despite exposure to many viruses, including SARS-CoV-2, which is life-threatening in individuals with impaired IFN-α/ß immunity. In leukocytes or fibroblasts stimulated in vitro, IRF1-dependent responses to IFN-γ are, both quantitatively and qualitatively, much stronger than those to IFN-α/ß. Moreover, IRF1-deficient mononuclear phagocytes do not control mycobacteria and related pathogens normally when stimulated with IFN-γ. By contrast, IFN-α/ß-dependent intrinsic immunity to nine viruses, including SARS-CoV-2, is almost normal in IRF1-deficient fibroblasts. Human IRF1 is essential for IFN-γ-dependent macrophagic immunity to mycobacteria, but largely redundant for IFN-α/ß-dependent antiviral immunity.

COVID-19 in hospitalized infants aged under 3 months: multi-center experiences across Turkey.

To investigate coronavirus disease 2019 (COVID-19) in infants aged 0 to 3 months because there is currently a significant gap in the literature on the subject. A cross-sectional study was conducted with the involvement of 19 medical centers across Turkey and 570 infants. The majority of the patients were male (58.2%), and the three most common symptoms were fever (78.2%), cough (44.6%), and feeding intolerance (39.9%). The results showed that a small percentage of infants had positive blood (0.9%) or urine cultures (10.2%). Most infants presented with fever (78.2%). Children without underlying conditions (UCs) had mostly a complicated respiratory course and a normal chest radiography. Significant more positive urine culture rates were observed in infants with fever. A higher incidence of respiratory support requirements and abnormal chest findings were seen in infants with chronic conditions. These infants also had a longer hospital stay than those without chronic conditions.  Conclusions: Our study discloses the clinical observations and accompanying bacterial infections found in infants aged under 3 months with COVID-19. These findings can shed light on COVID-19 in infancy for physicians because there is limited clinical evidence available. What is Known: • COVID-19 in infants and older children has been seen more mildly than in adults. • The most common symptoms of COVID-19 in infants are fever and cough, as in older children and adults. COVID-19 should be one of the differential diagnoses in infants with fever. What is New: • Although most infants under three months had fever, the clinical course was uneventful and respiratory complications were rarely observed in healthy children. • Infants with underlying conditions had more frequent respiratory support and abnormal chest radiography and stayed longer in the hospital.

Evaluation of 601 children with multisystem inflammatory syndrome (Turk MISC study).

PURPOSE: Due to its link with the 2019 coronavirus, the multisystem inflammatory syndrome in children (MISC) has garnered considerable international interest. The aim of this study, in which MISC patients were evaluated multicenter, and the data of the third period of the Turk-MISC study group, to compare the clinical and laboratory characteristics and outcomes of MISC patients who did and did not require admission to an intensive care unit (ICU). METHODS: This retrospective multicenter observational study was carried out between June 11, 2021, and January 01, 2022. The demographics, complaints, laboratory results, system involvements, and outcomes of the patients were documented. RESULTS: A total of 601 patients were enrolled; 157 patients (26.1%) required hospitalization in the intensive care unit (ICU). Median age was 8 years (interquartile range (IQR) 4.5-11.3 years. The proportion of Kawasaki disease-like features in the ICU group was significantly higher than in the non-ICU group (56.1% vs. 43.2% p = 0.006). The ICU group had considerably lower counts of both lymphocytes and platelets (lymphocyte count 900 vs. 1280 cells × µL, platelet count 153 vs. 212 cells × 103/ µL, all for p< 0.001). C-reactive protein, procalcitonin, and ferritin levels were significantly higher in the ICU group (CRP 164 vs. 129 mg/L, procalcitonin 9.2 vs. 2.2 µg/L, ferritin 644 vs. 334 µg/L, all for p< 0.001). Being between ages 5-12 and older than 12 increased the likelihood of hospitalization in the ICU by four [95% confidence intervals (CI)1.971-8.627] and six times (95% CI 2.575-14.654), respectively, compared to being between the ages 0-5. A one-unit increase in log D-dimer (µg/L) and log troponin (ng/L) was also demonstrated to increase the need for intensive care by 1.8 (95% CI 1.079-3.233) and 1.4 times (95% CI 1.133-1.789), respectively.     Conclusion: By comparing this study to our other studies, we found that the median age of MISC patients has been rising. Patients requiring an ICU stay had considerably higher levels of procalcitonin, CRP, and ferritin but significantly lower levels of lymphocyte and thrombocyte. In particular, high levels of procalcitonin in the serum might serve as a valuable laboratory marker for anticipating the need for intensive care. WHAT IS KNOWN: • Lymphopenia and thrombocytopenia were an independent predictor factors in patients with MISC who needed to stay in intensive care unit. • The possibility of the need to stay in the intensive care unit in patients with MISC who had Kawasaki disease-like findings was controversial compared with those who did not. WHAT IS NEW: • A one-unit increase log D dimer and log troponin was demonstrated to require for intensive care unit by 1.8 and 1.4 times, respectively. • Serum procalcitonin levels had the best performance to predict stay in the intensive care unit stay.

COVID-19 associated multisystemic inflammatory syndrome in 614 children with and without overlap with Kawasaki disease-Turk MIS-C study group.

Multisystemic inflammatory syndrome (MIS-C) diagnosis remains difficult because the clinical features overlap with Kawasaki disease (KD). The study aims to highlight the clinical and laboratory features and outcomes of patients with MISC whose clinical manifestations overlap with or without KD. This study is a retrospective analysis of a case series designed for patients aged 1 month to 18 years in 28 hospitals between November 1, 2020, and June 9, 2021. Patient demographics, complaints, laboratory results, echocardiographic results, system involvement, and outcomes were recorded. A total of 614 patients were enrolled; the median age was 7.4 years (interquartile range (IQR) 3.9-12 years). A total of 277 (45.1%) patients with MIS-C had manifestations that overlapped with KD, including 92 (33.3%) patients with complete KD and 185 (66.7%) with incomplete KD. Lymphocyte and platelet counts were significantly lower in patients with MISC, overlapped with KD (lymphocyte count 1080 vs. 1280 cells × µL, p = 0.028; platelet count 166 vs. 216 cells × 103/µL, p < 0.001). The median serum procalcitonin levels were statistically higher in patients overlapped with KD (3.18 vs. 1.68 µg/L, p = 0.001). Coronary artery dilatation was statistically significant in patients with overlap with KD (13.4% vs. 6.8%, p = 0.007), while myocarditis was significantly more common in patients without overlap with KD features (2.6% vs 7.4%, p = 0.009). The association between clinical and laboratory findings and overlap with KD was investigated. Age > 12 years reduced the risk of overlap with KD by 66% (p < 0.001, 95% CI 0.217-0.550), lethargy increased the risk of overlap with KD by 2.6-fold (p = 0.011, 95% CI 1.244-5.439), and each unit more albumin (g/dl) reduced the risk of overlap with KD by 60% (p < 0.001, 95% CI 0.298-0.559). CONCLUSION: Almost half of the patients with MISC had clinical features that overlapped with KD; in particular, incomplete KD was present. The median age was lower in patients with KD-like features. Lymphocyte and platelet counts were lower, and ferritin and procalcitonin levels were significantly higher in patients with overlap with KD. WHAT IS KNOWN: • In some cases of MIS-C, the clinical symptoms overlap with Kawasaki disease. • Compared to Kawasaki disease, lymphopenia was an independent predictor of MIS-C. WHAT IS NEW: • Half of the patients had clinical features that overlapped with Kawasaki disease. • In patients whose clinical features overlapped with KD, procalcitonin levels were almost 15 times higher than normal. • Lethargy increased the risk of overlap with KD by 2.6-fold in MIS-C patients. • Transient bradycardia was noted in approximately 10% of our patients after initiation of treatment.

Multisystem inflammatory syndrome in children associated with COVID-19 in 101 cases from Turkey (Turk-MISC study).

AIM: Multisystem inflammatory syndrome in children (MIS-C) may cause shock and even death in children. The aim of this study is to describe the clinical features, laboratory characteristics and outcome of children diagnosed with MIS-C in 25 different hospitals in Turkey. METHODS: The retrospective study was conducted between 8 April and 28 October 2020 in 25 different hospitals from 17 cities. Data were collected from patients' medical records using a standardised form. Clinical and laboratory characteristics and outcomes according to different age groups, gender and body mass index percentiles were compared using multivariate logistic regression analysis. RESULTS: The study comprised 101 patients, median age 7 years (interquartile range (IQR) 4.6-9.3); 51 (50.5%) were boys. Reverse-transcriptase polymerase chain reaction (PCR) assay was positive in 21/100 (21%) patients; 62/83 (74.6%) patients had positive serology for SARS-CoV-2. The predominant complaints were fever (100%), fatigue (n = 90, 89.1%), and gastrointestinal symptoms (n = 81, 80.2%). Serum C-reactive protein (in 101 patients, median 165 mg/L; range 112-228), erythrocyte sedimentation rate (73/84, median 53 mm/s; IQR 30-84) and procalcitonin levels (86/89, median 5 µg/L; IQR 0.58-20.2) were elevated. Thirty-eight patients (37.6%) required admission to intensive care. Kawasaki disease (KD) was diagnosed in 70 (69.3%) patients, 40 of whom had classical KD. Most patients were treated with intravenous immunoglobulin (n = 92, 91%) and glucocorticoids (n = 59, 58.4%). Seven patients (6.9%) died. CONCLUSION: The clinical spectrum of MIS-C is broad, but clinicians should consider MIS-C in the differential diagnosis when persistent fever, fatigue and gastrointestinal symptoms are prominent. Most patients diagnosed with MIS-C were previously healthy. Immunomodulatory treatment and supportive intensive care are important in the management of cases with MIS-C. Glucocorticoids and intravenous immunoglobulins are the most common immunomodulatory treatment options for MIS-C. Prompt diagnosis and prompt treatment are essential for optimal management.

A Rare Presentation of Neurobrucellosis in a 6-Year-Old Pediatric Patient with Sagittal Sinus Thrombosis.

Brucellosis is one of the most common zoonosis worldwide. It is still endemic in many regions of the world. A 6-year-old female was admitted to the emergency department (ED) due to a sudden change in consciousness, urinary incontinence, vomiting, and difficulty in walking. Neurological examination demonstrated abducens nerve paralysis, mild-to-moderate motor deficit in hemiparesis in the left arm. Brain magnetic resonance imaging showed a hemorrhagic focus at the right frontal lobe and thrombosis in the superior sagittal sinus of the brain. The diagnosis of neurobrucellosis was confirmed by identifying Brucella spp. in the blood culture on the day 6 of pediatric intensive care unit admission; thus, trimethoprim-sulfamethoxazole and rifampicin, and ceftriaxone were promptly initiated. Despite neuroprotective management and acetazolamide, the patient's neurological problems and high intracranial pressure (ICP) persisted. An external ventricular drainage tube and a Codman ICP monitor were placed to be on the consent vigilance of the patient's neurological condition. The patient's ICP continued to increase despite the current treatment regimen; therefore, a decompressive bitemporal craniectomy was performed. The ICP level of the patient returned to its normal range immediately after the craniectomy. The patient did not have any notable neurologic sequelae at the first-year follow-up. Neurobrucellosis is a rare complication of systemic brucellosis and may present as meningitis, encephalitis, myelitis, radiculitis, and/or neuritis. Herein, we describe a six-year-old girl with brucellosis complicated with cerebral vein thrombosis. This case illustrates the need for close monitoring of patients with unexplained neurological signs or symptoms for brucellosis in endemic areas.

A Snapshot of Pediatric Patients with COVID-19 in a Pandemic Hospital.

AIM: Reports describing coronavirus disease 2019 (Covid-19) in children are fewer than adult studies due to milder clinical picture. We aimed to share our experience at a single center with an emphasis on collective decision making. MATERIALS AND METHODS: A suspected case was defined as the presence of symptoms suggestive of COVID-19 and/or positive contact history. SARS-CoV-2 PCR positive patients were defined as confirmed COVID-19. Between March 12, 2020, and May 15, 2020, all children presenting with fever, cough, or respiratory difficulty were investigated for COVID-19. A total of 719 children were examined at outpatient clinics, and 495 were tested with polymerase chain reaction (PCR) for suspicion of COVID-19. A team was organized for monitoring and treating patients either as outpatients or hospitalization. Patients were evaluated in terms of age, gender, travel history, epidemiological history, clinical symptoms and signs, laboratory and radiological findings, treatment, and outcome. RESULTS: Sixty patients were hospitalized for suspicion of COVID-19. Forty-three patients were diagnosed as probable or confirmed COVID-19. 21 of 43 patients (48.8%) were PCR confirmed. The remaining 22 were diagnosed by epidemiologic history, clinical assessment, and computerized thorax tomography (CT) findings. The median age was 126 and 78.5 months in PCR positives and PCR negatives, respectively and the youngest patient was a 28 days old baby. Nineteen of the patients had an upper respiratory infection (44.1%). Although five patients had no clinical signs, chest X-ray, or CT revealed pneumonia. CONCLUSIONS: As previously reported, the clinical manifestations of COVID-19 in children are mostly mild. Even very young kids can become infected following exposure to sick family members. International and local guidelines are valuable for decision making since it is a new disease. A combination of chest disease, infectious diseases, and emergency care physicians approach will aid the appropriate management of cases.

Ventriculoperitoneal shunt infections and re-infections in children: a multicentre retrospective study.

PURPOSE: Ventriculoperitoneal shunt (VPS) is the most common treatment modality for hydrocephalus. However, VPS infection is a common and serious complication with high rates of mortality and morbidity. The objective of this study was to investigate causative agents and the management of VPS infections and to identify risk factors for re-infection in children. MATERIALS AND METHODS: Retrospective, multicentre study on patients with VPS infection at paediatric and neurosurgery departments in four tertiary medical centres in Turkey between January 2011 and September 2014. RESULTS: A total of 290 patients with VPS infections were identified during the study period. The aetiology of hydrocephalus was congenital malformations in 190 patients (65.5%). The most common symptom of shunt infection was fever in 108 (37.2%) cases. At least one pathogen was identified in 148 VPS infections (51%). The most commonly isolated pathogen was coagulase-negative staphylococci, which grew in 63 cases (42.5%), followed by Pseudomonas aeruginosa in 22 cases (14.9%), Klebsiella pneumoniae in 15 cases (10.1%), and Staphylococcus aureus in 15 cases (10.1). The median duration of VPS infection was 2 months (range, 15 days to 60 months) after insertion of the shunt, with half (49.8%) occurring during the first month. VPS infection was treated by antibiotics and shunt removal in 211 cases (76.4%) and antibiotics alone without shunt removal in 65 patients (23.5%). Among the risk factors, CSF protein level greater than 100 mg/dL prior to VPS insertion was associated with a potential risk of re-infection (OR, 1.65; p =.01). CONCLUSION: High protein levels (>100 mg/dL) before the re-insertion of a VPS may be a risk factor for VPS re-infection.

Are Growing Pains Related to Vitamin D Deficiency? Efficacy of Vitamin D Therapy for Resolution of Symptoms.

OBJECTIVES: The aim of this study was to investigate the 25-hydroxyvitamin D [25(OH)D] status of children with growing pains and to evaluate the efficacy of vitamin D treatment on the resolution of pain symptoms. SUBJECTS AND METHODS: One hundred and twenty children with growing pains were included in a prospective cohort study. Serum 25(OH)D and bone mineral levels were measured in all subjects at the time of enrollment. The pain intensity of those with vitamin D deficiency was measured using a pain visual analog scale (VAS). After a single oral dose of vitamin D, the pain intensity was remeasured by means of the VAS at 3 months. The 25(OH)D levels and VAS scores before and after oral vitamin D administration were compared by means of a paired Student's t test. RESULTS: In the 120 children with growing pains, vitamin D insufficiency was noted in 104 (86.6%). Following vitamin D supplementation, the mean 25(OH)D levels increased from 13.4 ± 7.2 to 44.5 ± 16.4 ng/ml, the mean pain VAS score decreased from 6.8 ± 1.9 to 2.9 ± 2.5 cm (a mean reduction of -3.8 ± 2.1, p < 0.001) and the difference was statistically significant. CONCLUSION: Supplementation with oral vitamin D resulted in a significant reduction in pain intensity among these children with growing pains who had hypovitaminosis D.

Tiny hair tuft: a clue for occipital cephalocele.

Recurrent meningitis is a rare problem and can be due to alterations in immune system, or craniospinal defect. Any clue either in patient's history or physical examination would be helpful for avoiding unnecessary and tiring tests. Here we present the case of a child with recurrent bacterial meningitis who had an unnoticed hair tuft on the occipital region. The final diagnosis was occipital cephalocele with a rare presentation of a tiny tuft of hair.

Pathogens in Pediatric Septic Arthritis: A Multi-Center Study in Turkiye (PEDSART Study).

OBJECTIVES: Septic arthritis (SA) is a serious bacterial infection that must be treated efficiently and timely. The large number of culture-negative cases makes local epidemiological data important. Accordingly, this study aimed to evaluate the etiology, clinical characteristics, and therapeutic approach of SA in children in Turkiye, emphasizing the role of real-time polymerase chain reaction (PCR) techniques in the diagnosis. METHODS: In this multi-center, prospective study, children hospitalized due to SA between February 2018 and July 2020 in 23 hospitals in 14 cities in Turkiye were included. Clinical, demographic, laboratory, and radiological findings were assessed, and real-time PCR was performed using synovial fluid samples. RESULTS: Seventy-five children aged between 3 and 204 months diagnosed with acute SA were enrolled. Joint pain was the main complaint at admission, and the most commonly involved joints were the knees in 58 patients (77.4%). The combination of synovial fluid culture and real-time PCR detected causative bacteria in 33 patients (44%). In 14 (18.7%) patients, the etiological agent was demonstrated using only PCR. The most commonly isolated etiologic agent was Staphylococcus aureus, which was detected in 22 (29.3%) patients, while Streptococcus pyogenes was found in 4 (5.3%) patients and Kingella kingae in 3 (4%) patients. Streptococcus pyogenes and Kingella kingae were detected using only PCR. Most patients (81.3%) received combination therapy with multiple agents, and the most commonly used combination was glycopeptides plus third-generation cephalosporin. CONCLUSIONS: Staphylococcus aureus is the main pathogen in pediatric SA, and with the use of advanced diagnostic approaches, such as real-time PCR, the chance of diagnosis increases, especially in cases due to Kingella kingae and Streptococcus pyogenes.

Potential cost-effectiveness of pneumococcal conjugate vaccine (PCV) in Turkey.

BACKGROUND: Pneumococcal infection is an important and preventable cause of morbidity and mortality. The Turkish government introduced 7-valent pneumococcal conjugate vaccine (PCV) into the national immunization program in 2009. This suggests that replacing 7-valent PCV with a higher-valent version could at least maintain "standard of care" if not improve it, and that it could be affordable. OBJECTIVES AND METHODS: The aim of this analysis was to assess the potential direct cost-effectiveness of 13-valent PCV in Turkey, a country with a birth cohort of 1.4 million, against a "no vaccine" state, against the default 7-valent PCV state, and against a 10-valent PCV state, using a published cohort model with a 5-year horizon. RESULTS AND CONCLUSIONS: The cost per life-year gained is below the 1 × per-capita gross domestic product threshold across large changes in key input parameters, indicating that the model is stable and suggesting that any PCV would be very cost-effective in a Turkish national pediatric immunization schedule.

Community-acquired S. aureus infection in childhood: a multi-center study.

BACKGROUND: The prevalence of community-acquired methicillin-resistant S. aureus (CA-MRSA) has been increasing worldwide. We aimed to investigate the prevalence of MRSA in community-acquired S. aureus infections, the risk factors for CA-MRSA infection and the clinical features of CA-MRSA. METHODS: A multi-center study with prospective and retrospective sections was conducted. Patients ≥ 3 months old and ≤18 years of age who were diagnosed with community-acquired S. aureus infections were included in this study and the patients` information were reviewed from the medical and microbiological database of the hospital. A standard question form about living conditions and exposure risk factors was administered to the parents of patients. The CA-MRSA infections were compared with the methicillin-susceptible S. aureus (CAMSSA) infections in terms of the queried risk factors and clinical variables. RESULTS: We identified 334 pediatric patients with S. aureus infection, 58 (17.4%) had an infection with CAMRSA. The refugee rate was higher in the CA-MRSA group. There was no significant difference regarding the exposure risk. The treatment modalities and outcomes were similar. CONCLUSIONS: The study was not able to show reliable clinical variables or epidemiological risk factors except for being a refugee for CA-MRSA infections. Empirical antibiotic treatment should therefore be determined according to the local CA-MRSA prevalence in patients presenting with a possible staphylococcus infection.

The epidemiology and economic impact of varicella-related hospitalizations in Turkey from 2008 to 2010: a nationwide survey during the pre-vaccine era (VARICOMP study).

Varicella can cause complications that are potentially serious and require hospitalization. Our current understanding of the causes and incidence of varicella-related hospitalization in Turkey is limited and sufficiently accurate epidemiological and economical information is lacking. The aim of this study was to estimate the annual incidence of varicella-related hospitalizations, describe the complications, and estimate the annual mortality and cost of varicella in children. VARICOMP is a multi-center study that was performed to provide epidemiological and economic data on hospitalization for varicella in children between 0 and 15 years of age from October 2008 to September 2010 in Turkey. According to medical records from 27 health care centers in 14 cities (representing 49.3% of the childhood population in Turkey), 824 children (73% previously healthy) were hospitalized for varicella over the 2-year period. Most cases occurred in the spring and early summer months. Most cases were in children under 5 years of age, and 29.5% were in children under 1 year of age. The estimated incidence of varicella-related hospitalization was 5.29-6.89 per 100,000 in all children between 0-15 years of age in Turkey, 21.7 to 28 per 100,000 children under 1 year of age, 9.8-13.8 per 100,000 children under 5 years of age, 3.96-6.52 per 100,000 children between 5 and 10 years of age and 0.42 to 0.71 per 100,000 children between 10 and 15 years of age. Among the 824 children, 212 (25.7%) were hospitalized because of primary varicella infection. The most common complications in children were secondary bacterial infection (23%), neurological (19.1%), and respiratory (17.5%) complications. Secondary bacterial infections (p < 0.001) and neurological complications (p < 0.001) were significantly more common in previously healthy children, whereas hematological complications (p < 0.001) were more commonly observed in children with underlying conditions. The median length of the hospital stay was 6 days, and it was longer in children with underlying conditions (<0.001). The median cost of hospitalization per patient was $338 and was significantly higher in children with underlying conditions (p < 0.001). The estimated direct annual cost (not including the loss of parental work time and school absence) of varicella-related hospitalization in children under the age of 15 years in Turkey was $856,190 to $1,407,006. According to our estimates, 882 to 1,450 children are hospitalized for varicella each year, reflecting a population-wide occurrence of 466-768 varicella cases per 100,000 children. In conclusion, this study confirms that varicella-related hospitalizations are not uncommon in children, and two thirds of these children are otherwise healthy. The annual cost of hospitalization for varicella reflects only a small part of the overall cost of this disease, as only a very few cases require hospital admission. The incidence of this disease was higher in children <1 year of age, and there are no prevention strategies for these children other than population-wide vaccination. Universal vaccination is therefore the only realistic option for the prevention of severe complications and deaths. The surveillance of varicella-associated complications is essential for monitoring of the impact of varicella immunization.