Mehdi Yeganeh

Mutations in STAT3 and diagnostic guidelines for hyper-IgE syndrome

BACKGROUND The hyper-IgE syndrome (HIES) is a primary immunodeficiency characterized by infections of the lung and skin, elevated serum IgE, and involvement of the soft and bony tissues. Recently, HIES has been associated with heterozygous dominant-negative mutations in the signal transducer and activator of transcription 3 (STAT3) and severe reductions of T(H)17 cells. OBJECTIVE To determine whether there is a correlation between the genotype and the phenotype of patients with HIES and to establish diagnostic criteria to distinguish between STAT3 mutated and STAT3 wild-type patients. METHODS We collected clinical data, determined T(H)17 cell numbers, and sequenced STAT3 in 100 patients with a strong clinical suspicion of HIES and serum IgE >1000 IU/mL. We explored diagnostic criteria by using a machine-learning approach to identify which features best predict a STAT3 mutation. RESULTS In 64 patients, we identified 31 different STAT3 mutations, 18 of which were novel. These included mutations at splice sites and outside the previously implicated DNA-binding and Src homology 2 domains. A combination of 5 clinical features predicted STAT3 mutations with 85% accuracy. T(H)17 cells were profoundly reduced in patients harboring STAT3 mutations, whereas 10 of 13 patients without mutations had low (<1%) T(H)17 cells but were distinct by markedly reduced IFN-gamma-producing CD4(+)T cells. CONCLUSION We propose the following diagnostic guidelines for STAT3-deficient HIES. Possible: IgE >1000IU/mL plus a weighted score of clinical features >30 based on recurrent pneumonia, newborn rash, pathologic bone fractures, characteristic face, and high palate. Probable: These characteristics plus lack of T(H)17 cells or a family history for definitive HIES. Definitive: These characteristics plus a dominant-negative heterozygous mutation in STAT3.

Clinical, Immunological and Molecular Characteristics of 37 Iranian Patients with X-Linked Agammaglobulinemia

Background: X-linked agammaglobulinemia (XLA) is a hereditary immunodeficiency characterized by an early onset of recurrent bacterial infections, a profound deficiency of all immunoglobulin isotypes and a markedly reduced number of peripheral B lymphocytes. Eighty-five percent of the patients with this phenotype have mutations in Bruton’s tyrosine kinase (BTK) gene. Methods: To provide an informative outlook of clinical and immunological manifestations of XLA in Iran, 37 Iranian male patients with an age range of 1–34 years, followed over a period of 25 years, were studied. Twenty-four of the 37 patients were screened for BTK gene mutation using PCR-SSCP followed by direct sequencing. BTK protein expression assay was done by flow cytometry in 9 families. Results: All patients first presented with infectious diseases, the most common of which were respiratory tract infections. Eighteen different mutations were identified, 13 of which were novel: IVS1+5G>C, 1896G>A, 349delA, 1618C>T, 1783T>C, 2084A>G, 1346delT, 1351delGAG, 587A>G, IVS14–1G>A, IVS3+2T>C, 1482G>A, 1975C>A. Conclusion: The fact that we found a great number of novel mutations in a relatively limited number of patients underlines the heterogeneity of BTK mutations in the Iranian population. The large number of new mutations indicates that extended studies in this region would be rewarding.

Severe combined immunodeficiency: A cohort of 40 patients

Severe Combined Immunodeficiency (SCID) consists of a heterogeneous group of genetic disorders characterized by an arrest in T lymphocyte development which is variably associated with an abnormal differentiation of B and NK cells. In order to depict the clinical state of Iranian patients with SCID, records of forty patients were reviewed. Patients were classified based on the flow cytometry data in two groups of B− and B+. In thirty two families (80%) parents were consanguine and in 17 families (50%) there were affected members other than proband. We showed that autosomal forms of SCID might be more frequent due to higher rate of consanguineous marriages. Alongside several infective complications, complicated Bacillus Calmette‐Guérin (BCG) vaccination was documented in 18 cases (45%) following the routine vaccination at birth. BCG immunization is still a part of standard vaccination for newborns in developing countries; whereas in communities with a better health condition it could be held for a few months and performed for kids whose immune system sounds intact. We discuss where consanguine mating is common, a test of screening should be run timely. A complete blood count of cord blood could reveal lymphocytopenia at birth; this helps early diagnosis. Genetic consultation would help the families with affected members preventing new SCID offspring.

Analysis of RAB27A Gene in Griscelli Syndrome type 2: Novel Mutations Including a Deletion Hotspot

IntroductionGriscelli syndrome type 2 is an autosomal recessive disorder characterized by pigmentary dilution and occurrence of acute phases of hemophagocytosis. The disease is caused by mutations in RAB27A gene, coding a small GTPase involved in terminal phases of cytotoxic granule/melanosome exocytosis.Materials and methodsWe describe the result of mutation analysis among nine patients from seven non-related Persian families. We present four novel mutations including a deletion hot spot (514del 5).ConclusionThis hot spot is flanked by “direct repeats” of nucleotides, which are previously shown to be associated with areas of recurrent small deletions.

The clinical and laboratory survey of Iranian patients with Hyper-IgE syndrome

In order to determine the clinical and laboratory findings of Iranian patients with presumed hyper-immunoglobulin E syndrome (HIES), the medical records of 22 patients from 21 unrelated families, who had been registered in the Iranian Primary Immunodeficiency Registry, were observed. The median age of patients at the time of first symptom and at the time of diagnosis was 1 month and 52.5 months, respectively, with a median diagnosis delay of 70 months. 13 families had consanguineous marriages. IgE level was higher than 2000 IU/ml in all patients, ranging from >2000 to 80,000 IU/ml. The most commonly occurring manifestations were: eczema and dermatitis, pneumonia, upper respiratory tract infections, cutaneous abscesses, diarrhoea, deep abscesses, and otitis media. Other less frequent manifestations were: mucocutaneous candidiasis, sinusitis, cutaneous ulcers, Molluscum contagiosum, herpetic keratitis, onychomycosis, conjunctivitis, septic arthritis, and meningitis. Five patients were complicated by bronchiectasis due to recurrent pneumonia and 5 patients died because of severe infections and malignancy. The HIES is a multisystem disorder that affects especially cutaneous, respiratory, skeletal and the immune system. Although HIES is a rare condition, the recurrent infections should always raise a suspicion, which deserves further evaluation for detecting the syndrome.

Invasive aspergillosis in chronic granulomatous disease : report of 7 cases

Keywords Chronicgranulomatousdisease.CGD.InvasiveaspergillosisChronic granulomatous disease (CGD) is an inherited dis-order of the NADPH oxidase complex characterized byrecurrent bacterial and fungal infections. The underlyingdefect is an inability to generate reactive oxygen intermedi-ates and activation of intracellular proteases, which are keyelements in host defense [5]. The incidence of fungalinfections in CGD has been reported to be 20%, withAspergillus spp accounting for 78% of them [2]. We reportseven CGD patients with invasive aspergillosis (IA) anddescribetheirclinicalpicture(Table1). The diagnostic criteriafor CGD were abnormal nitroblue tetrazolium test (NBT),and/or dihydrorhodamin 123 (DHR) assay. The X-linkedform of CGD was suspected by the pattern of inheritance,abnormal NBT or mosaic DHR pattern in mothers.The mycological diagnosis was determined by micros-copy and culture of clinical samples.The median age at onset of CGD was 5 months (range2–24). The fungal infection appeared at the median age of72 months. In P4, aspergillosis was the first presentation.All patients presented febrile with the mean erythrocytesedimentation rate (ESR) of 80 mm/hr. Uncertain responsesto antibiotics and infiltrations on X-ray or CT-scan were thefirst indication of a fungal infection.The sites of infection were lungs, chest wall, brain, liverand lymph nodes. In P2 and P6, costal osteomyelitisresulted from contiguous spread of pulmonary and hepaticinfections, respectively.In five patients A. fumigatus was isolated whereas P5was affected by A. flavus. Deoxycholate amphotericin B(1 mg/kg/day) was the first line treatment. Itraconazole (5–10 mg/kg/day) and flucytosine (100 mg/kg/day) were usedas adjunctive. Prophylactic itraconazole reduces the risk offungal infections in CGD [3] but none of our patientsreceived it.Surgical debridement was used for all but P2. Threepatients recovered, and discharged on oral itraconazole.Other patients died because of an uncontrolled infectiousprocess. In P6 amphotericin B therapy led to an initialimprovement, however; he deteriorated within two monthsand passed away.IA is the most important cause of mortality in CGD [1]and A. fumigatus is the most frequent inciting organism [7].All of our patients presented during the first decade of lifewhich is lower than a previous study [8]. Although X-linked CGD is thought to be more susceptible to IA [7], ourresults show that autosomal forms are prone as well.

Genotype-phenotype correlation in Bruton's tyrosine kinase deficiency.

Brutons tyrosine kinase (Btk) belongs to the Tec family of nonreceptor protein tyrosine kinases. Mutations in the BTK gene cause X-linked agammaglobulinemia (XLA); a primary immunodeficiency disorder in human. No clear genotype-phenotype correlation has been established in XLA so far. To determine how differently mutations in BTK affect the severity of the disease and if BTK promoter polymorphic variant or intron 1 polymorphic variant in Tec, a cytoplasmic tyrosine kinase that might substitute for Btk, could contribute to the clinical phenotype, we analyzed the clinical and molecular findings in a cohort of XLA patients. Polymorphisms in BTK promoter and TEC intron 1 regions include substitutions of C>T (rs2071219) and T>C (rs2664019), respectively. Btk expression was evaluated by means of western immunoblotting and fluorescence-activated cell sorter analysis. Mutations were categorized as mild or severe and patients were evaluated for the clinical severity of disease. On the basis of the results, severe genotypes do not necessarily lead to severe phenotypes. More over, in a considerable number of patients with mild phenotype we showed a severe mutation with a tendency toward C substitution in the polymorphic site on TEC intron 1.

Progressive multifocal leukoencephalopathy in purine nucleoside phosphorylase deficiency.

Progressive multifocal leukoencephalopathy is a demyelinating disease caused by JC virus, an opportunistic infection of the central nervous system. Although the majority of cases are infected with the human immunodeficiency virus (HIV), other immunocompromised patients are also at risk. Purine nucleoside phosphorylase is an enzyme in the purine salvage pathway that reversibly converts inosine to hypoxanthine and guanosine to guanine. Purine nucleoside phosphorylase deficiency is a combined immunodeficiency with a profound cellular defect. Neurologic abnormalities are salient features of this syndrome. We describe for the first time a patient with this rare disorder presented with progressive multifocal leukoencephalopathy.

Toll-Like Receptor Stimulation Induces Higher TNF-α Secretion in Peripheral Blood Mononuclear Cells from Patients with Hyper IgE Syndrome

Hyper IgE syndromes (HIES) are primary immunodeficiency disorders of unknown pathogenesis. Patients are typically affected with ‘cold’ abscesses of the skin, recurrent cyst-forming pneumonia, chronic mucocutaneous candidiasis and other less frequent features such as progressive skeletal abnormalities. Defective signaling in the Toll-like receptor (TLR) pathways has been suggested as a responsible pathologic mechanism, however, in previous reports, 10 patients revealed no defect in inflammatory cytokine responses to different TLR ligands. Here, we report the increase in pro-inflammatory cytokines TNF-α and IL-8, following TLR2 and TLR4 stimulation in a larger cohort of 25 additional patients with HIES, and provide a meta-analysis of the TLR data in HIES.

Debilitating progressive encephalitis in a patient with BTK deficiency

X-linked agammaglobulinemia (XLA), also known as Brutons tyrosine kinase (BTK) deficiency, is a primary antibody deficiency, characterized by low number of B cells, agammaglobulinemia and increased susceptibility to a variety of infections. Herein, we report a case of XLA with confirmed BTK mutation that developed neurological deficits. While we could not detect any responsible microorganism in spite of comprehensive workup, brain magnetic resonance imaging revealed moderate brain atrophy. The diagnosis of progressive encephalitis was made for this patient. Patients with XLA have a higher chance of encephalitis compared with other primary antibody deficiencies. Given the violent nature of encephalitis, it is a concern among XLA patients.