Interleukin-1 Receptor-Associated Kinase 4 Deficiency in a Greek Teenager.

BACKGROUND: Human interleukin- (IL-) 1 receptor-associated kinase 4 (IRAK-4) deficiency is a recently described primary immunodeficiency. It is a rare, autosomal recessive immunodeficiency that impairs toll/IL-1R immunity, except for the toll-like receptor (TLR) 3- and TLR4-interferon alpha (IFNA)/beta (IFNB) pathways. Case Report. We report the first patient in Greece with IRAK-4 deficiency. From the age of 8 months, she presented with recurrent infections of the upper and lower respiratory tract and skin abscesses. For this, she had been repeatedly hospitalized and treated empirically with intravenous antibiotics. No severe viral, mycobacterial, or fungal infections were noted. Her immunological laboratory evaluation revealed low serum IgA and restored in subsequent measurements; normal IgG, IgM, and IgE; and normal serum IgG subclasses. Peripheral blood immunophenotyping by flow cytometry and dihydrorhodamine (DHR) test revealed normal counts. She was able to make functional antibodies against vaccine antigens, including tetanus and diphtheria. She was administered with empirical IgG substitution for 5 years until the age of 12 years, and she has never experienced invasive bacterial infections so far. DNA analysis revealed a heterozygous variant in the patient: c.823delT (p.S275fs ∗ 13 at protein level) in the IRAK4 gene. CONCLUSIONS: The importance of clinical suspicion is emphasized in order to confirm the diagnosis by IRAK4 gene sequencing and provide the appropriate treatment for this rare primary immunodeficiency, as soon as possible.

Juvenile Recurrent Parotitis: The Role of Sialendoscopy.

Juvenile recurrent parotitis (JRP) is a recurrent parotid inflammation of nonobstructive, nonsuppurative nature. It manifests in childhood and usually resolves after puberty but may also persist into adulthood. JRP is characterized by recurrent episodes of unilateral or/and bilateral parotid swelling with pain, reduction of salivary secretion, swallowing difficulty, fever, and malaise. The cause of this condition remains obscure. Throughout the last two decades, many therapeutic methods have been used in order to reduce the frequency and severity of JRP. During the acute episodes, conservative approaches (antibiotics, analgesics, sialogogues, massage of the parotid gland, and mouth rinses) are used. Parotidectomy has been suggested in rare selective occasions. Recently, a promising concept of sialendoscopy, which is a minimal invasive endoscopic technique, has been applied. This review outlines the literature on JRP focusing on methods and challenges in diagnosing JRP along with the differential diagnosis of JRP and the function of the parotid during JRP. In addition, we describe the treatment options for JRP, pointing out the importance of sialendoscopy as a diagnostic and treatment procedure that offers improvement in patients' daily life.

The Role of TLR4 Asp299Gly and TLR4 Thr399Ile Polymorphisms in the Pathogenesis of Urinary Tract Infections: First Evaluation in Infants and Children of Greek Origin.

Urinary tract infections are one of the most common and serious bacterial infections in a pediatric population. So far, they have mainly been related to age, gender, ethnicity, socioeconomic level, and the presence of underlying anatomical or functional, congenital, or acquired abnormalities. Recently, both innate and adaptive immunities and their interaction in the pathogenesis and the development of UTIs have been studied. The aim of this study was to assess the role and the effect of the two most frequent polymorphisms of TLR4 Asp299Gly and Thr399Ile on the development of UTIs in infants and children of Greek origin. We studied 51 infants and children with at least one episode of acute urinary tract infection and 109 healthy infants and children. We found that 27.5% of patients and 8.26% of healthy children carried the heterozygote genotype for TLR4 Asp299Gly. TLR4 Thr399Ile polymorphism was found to be higher in healthy children and lower in the patient group. No homozygosity for both studied polymorphisms was detected in our patients. In the group of healthy children, a homozygote genotype for TLR4 Asp299Gly (G/G) as well as for TLR4 Thr399Ile (T/T) was showed (1.84% and 0.92 respectively). These results indicate the role of TLR4 polymorphism as a genetic risk for the development of UTIs in infants and children of Greek origin.

Altered Expression of TLR2 and TLR4 on Peripheral CD14+ Blood Monocytes in Children with Urinary Tract Infection.

Urinary tract infection (UTI) is the second most common bacterial infection, after otitis media, in infants and children. The mechanisms of disease susceptibility and the role of immunity in the pathogenesis of UTI in children have been evaluated. In recent years, Toll-Like Receptors (TLRs) have been recognized as specific components of the innate immune system constituting important mediators in host immune recognition. The aim of the present study was to determine ΤLR2 and TLR4 expression during the acute phase of UTI in infants and children by measuring the CD14/TLR2 and CD14/TLR4 expression on monocytes. We also attempted to compare the TLRs expression with the immunological status of the patients to healthy children. The study group consisted of 60 children (36 females and 24 males) and the control group included 60 age-matched pediatric subjects (27 females and 33 males). In our study, no antibody deficiency was found either in the children with UTI or in healthy subjects. There might be a connection between low IgA, IgG, and IgG subclasses serum levels and UTI as there was a statistically significant difference between patients and healthy children. A higher expression of CD14/TLR2 was revealed in patients (90,07%) compared to controls (85,48%) as well as CD14/TLR4 in patients (90,53%) compared to controls (87,25%) (statistically significant difference, p < 0,05). The results of this study could provide new understanding of UTIs' pathogenesis in children.