Expanding the mutation spectrum in ICF syndrome: Evidence for a gender bias in ICF2.

BACKGROUND: Immunodeficiency, centromeric instability, and facial anomalies (ICF) syndrome is a rare, genetically heterogeneous, autosomal recessive disorder. Patients suffer from recurrent infections caused by reduced levels or absence of serum immunoglobulins. Genetically, 4 subtypes of ICF syndrome have been identified to date: ICF1 (DNMT3B mutations), ICF2 (ZBTB24 mutations), ICF3 (CDCA7 mutations), and ICF4 (HELLS mutations). AIM: To study the mutation spectrum in ICF syndrome. MATERIALS AND METHODS: Genetic studies were performed in peripheral blood lymphocyte DNA from suspected ICF patients and family members. RESULTS: We describe 7 ICF1 patients and 6 novel missense mutations in DNMT3B, affecting highly conserved residues in the catalytic domain. We also describe 5 new ICF2 patients, one of them carrying a homozygous deletion of the complete ZBTB24 locus. In a meta-analysis of all published ICF cases, we observed a gender bias in ICF2 with 79% male patients. DISCUSSION: The biallelic deletion of ZBTB24 provides strong support for the hypothesis that most ICF2 patients suffer from a ZBTB24 loss of function mechanism and confirms that complete absence of ZBTB24 is compatible with human life. This is in contrast to the observed early embryonic lethality in mice lacking functional Zbtb24. The observed gender bias seems to be restricted to ICF2 as it is not observed in the ICF1 cohort. CONCLUSION: Our study expands the mutation spectrum in ICF syndrome and supports that DNMT3B and ZBTB24 are the most common disease genes.

B-cell subsets in patients with transient hypogammaglobulinemia of infancy, partial IgA deficiency, and selective IgM deficiency.

BACKGROUND: The pathogenesis of some primary humoral immunodeficiencies, such as transient hypogammaglobulinemia of infancy (THI) and immunoglobulin (Ig) A deficiency, remains unknown and can render diagnosis problematic. OBJECTIVE: In the present study, we used flow cytometry to analyze peripheral blood B-cell subsets in patients with THI and unclassified hypogammaglobulinemia (UCH), partial IgA deficiency, and selective IgM deficiency. METHODS: The study population comprised 41 patients with hypogammaglobulinemia (THI, 18; UCH, 23), 16 patients with partial IgA deficiency, and 16 patients with selective IgM deficiency who were admitted to Ankara University Department of Pediatric Immunology-Allergy between January 2010 and April 2011, as well as 29 healthy controls. B-cell subsets were examined according to the EUROclass classification. RESULTS: Age at diagnosis in the hypogammaglobulinemia group ranged between-14 months and 13 years (median, 26 months). Naive B-cell percentages were significantly higher and activated B-cell values lower in the THI patients than in the UCH patients and age-matched healthy controls. Nonswitched (IgM+CD27+IgD+) memory B-cell values were found to be significantly lower in patients with selective IgM deficiency than in healthy controls. No significant differences in B-cell subsets were found in patients with partial IgA deficiency. CONCLUSIONS: Previous reports show that reduced class-switched memory B cell values are associated with CVID, THI, and selective IgA deficiency. Our findings did not support these reports. Furthermore, we observed that naive B cell values were higher in patients with THI. A maturation defect could play a role in the pathogenesis of THI.

Demethylation analysis of the FOXP3 locus shows quantitative defects of regulatory T cells in IPEX-like syndrome.

Immune dysregulation, Polyendocrinopathy, Enteropathy X-linked (IPEX) syndrome is a unique example of primary immunodeficiency characterized by autoimmune manifestations due to defective regulatory T (Treg) cells, in the presence of FOXP3 mutations. However, autoimmune symptoms phenotypically resembling IPEX often occur in the absence of detectable FOXP3 mutations. The cause of this "IPEX-like" syndrome presently remains unclear. To investigate whether a defect in Treg cells sustains the immunological dysregulation in IPEX-like patients, we measured the amount of peripheral Treg cells within the CD3(+) T cells by analysing demethylation of the Treg cell-Specific-Demethylated-Region (TSDR) in the FOXP3 locus and demethylation of the T cell-Specific-Demethylated-Region (TLSDR) in the CD3 locus, highly specific markers for stable Treg cells and overall T cells, respectively. TSDR demethylation analysis, alone or normalized for the total T cells, showed that the amount of peripheral Treg cells in a cohort of IPEX-like patients was significantly reduced, as compared to both healthy subjects and unrelated disease controls. This reduction could not be displayed by flow cytometric analysis, showing highly variable percentages of FOXP3(+) and CD25(+)FOXP3(+) T cells. These data provide evidence that a quantitative defect of Treg cells could be considered a common biological hallmark of IPEX-like syndrome. Since Treg cell suppressive function was not impaired, we propose that this reduction per se could sustain autoimmunity.

Bacille Calmette-Guérin lymphadenitis and recurrent oral candidiasis in an infant with a new mutation leading to interleukin-12 receptor beta-1 deficiency.

Mendelian susceptibility to mycobacterial diseases (MSMD) is a rare syndrome characterized by predisposition to infections caused by weakly virulent mycobacteria, such as those in bacille Calmette-Guérin (BCG) vaccine and environmental mycobacteria. Salmonellosis has been reported in almost half of affected patients. Patients are also vulnerable to Mycobacterium tuberculosis infection. Several other infectious diseases may occur, albeit rarely. Mucocutaneous candidiasis is more common. Interleukin-12 receptor beta1 (IL-12Rbeta1) deficiency is the most frequent genetic cause of MSMD. Here, we describe an infant with a single episode of BCG lymphadenitis who also suffered from recurrent oral candidiasis. Genetic analysis revealed a new homozygous mutation (64+1G>T) in the IL12RB1 gene that caused complete IL-12R1beta1 deficiency. IL-12Rbeta1 deficiency should be considered in patients with BCG infection, even in those who experience a single episode of BCG lymphadenitis or recurrent mucocutaneous candidiasis. Every attempt should be made to heighten awareness in countries where BCG vaccination is performed.

CD27 expression on lymphocyte and sCD27 levels in children with asthma.

BACKGROUND: CD27, a lymphocyte specific member of the Tumour Necrosis Factor- Receptor (TNF-R) family is expressed on the majority of peripheral blood T cells. Activation of T cells via TCR/CD3 induces high CD27 surface expression and release of a soluble form (sCD27) of the molecule. sCD27 level increases in patients suffering from a variety of chronic inflammatory diseases. In the present study we aimed to measure both the serum sCD27 levels and CD27 expression on T cells in asthmatic patients, to evaluate the state of this molecule in allergic inflammation. METHODS: Forty-three patients with asthma were included in to the study. CD27 molecule expression and soluble form of this molecule were analysed in atopic asthmatic (n:17) and non-atopic asthmatic (n:13) patients receiving inhaled corticosteroid treatment, in asthmatic patients whose treatment ceased at least for 6 months (n:13) and healthy control subjects (n:14). RESULTS: There were no differences in the expression of CD27 molecule on peripheral blood lymphocyte nor in its soluble form sCD27 levels in sera between the atopic asthmatic and non-atopic asthmatic patients receiving ICS treatment, treatment free asthmatic patients and healthy control subjects. CONCLUSIONS: Neither the soluble form of CD27 nor its expression on T cells seem to be a reliable marker of atopic or non-atopic asthmatic inflammation.

An intensive approach to the treatment of disseminated BCG infection in a SCID patient.

There is an appreciable mortality associated with BMT in patients with SCID and advanced BCG infection. We present a girl with T-B+ SCID complicated by spina ventosa and disseminated BCG osteitis after receiving a fully matched sibling marrow transplant. Considerable progression characterised by two clinical activations and multiple pleural and perivertebral abscess formations occurred with conventional anti-mycobacterial chemotherapy. She finally recovered with full immune reconstitution after BMT and intensive treatment comprising five conventional and alternative agents that she received for 36 months. No side-effects and/or complications have been seen other than hearing loss.

657del5 mutation in the NBS1 gene is associated with Nijmegen breakage syndrome in a Turkish family.

We report on a consanguineous Turkish family whose first son died of anal atresia and whose second son presented with severe pre- and post-natal growth retardation as well as striking microcephaly, immunodeficiency, congenital heart disease, chromosomal instability and rhabdomyosarcoma in the anal region. The proband was found to carry the homozygous 657del5 mutation in the NBS1 gene, which is responsible for Nijmegen breakage syndrome (NBS) in most of the Slav populations. Our family, the first diagnosed with NBS in the Turkish population, represents one of the most severely affected examples of the syndrome, with profound pre- and post-natal growth retardation associated with structural abnormalities, and expands the clinical spectrum of this rare disorder.

Are uraemic children immunologically compromised?

BACKGROUND: Various immunological abnormalities leading to impaired immune status have been described in uraemic adults; however, few data are available for uraemic children. METHODS: In this study, peripheral blood total lymphocyte count and lymphocyte subsets (CD3+, CD4+, CD8+, CD16+, CD20+) were evaluated, skin tests with PPD and Candida antigens were performed, and serum immunoglobulin (IgG, IgA, IgM) and complement (C3, C4) levels were measured in 30 children with end-stage renal failure (10 before dialysis, 10 on continuous ambulatory peritoneal dialysis, and 10 on haemodialysis) and the results compared with those of 15 healthy controls. RESULTS: The data showed significant lymphopenia in predialysis and haemodialysis groups. No significant change was observed in the CD4+/CD8+ ratio or in the percentages of lymphocyte subsets in either group studied, while the absolute values of some lymphocyte subsets were significantly lower in all groups as compared with controls. In skin test evaluation, only the patients in the predialysis group showed a significantly decreased response to Candida antigen. The serum immunoglobulin levels were significantly decreased in the continuous ambulatory peritoneal dialysis group as compared with the control group. CONCLUSION: Our results, together with those of other paediatric studies, reported in the literature, suggest that uraemic children are not immunocompromised, though the effects of uraemia may cause some variation in their immune status.

Serum levels and differential expression of CD44 in childhood leukemia and malignant lymphoma: correlation with prognostic criteria and survival.

BACKGROUND: The CD44, a cell surface proteoglycan, participates in a variety of function including tumor dissemination and metastasis. However, there are no available data on the prognostic significance of CD44 expression of tumor tissue correlated with serum sCD44 level in childhood leukemias and lymphomas. METHODS: Serum levels and leukemic cell tumor tissue expression of CD44 were detected in 54 children with acute leukemia and malignant lymphoma. Serum samples were obtained from all patients before treatment and during remission. Twelve age-matched healthy children were included as a control group. RESULTS: The serum CD44 levels were significantly higher in patients with Hodgkin's disease (HD), non-Hodgkin's lymphoma (NHL), Burkitt's lymphoma (BL) and acute lymphoblastic leukemia (ALL) than those in the control group. The median values were 1627.0, 1336.0, 1318.5, 1730.4, 902.7 ng/mL, respectively, and P<0.001, P<0.01, P<0.01, P<0.05 in comparisons, respectively. However, there was no significant difference between acute myeloid leukemia (AML) and the control group (median values: 900.3 and 902.7 ng/mL, respectively, P>0.05). Serum sCD44 levels significantly declined in HD, NHL and ALL patients who were in complete remission (median values: 684.0, 573.8 and 1101.1 ng/mL, respectively, P<0.05 in each comparison). Patients with HD had higher levels of serum sCD44 and correlated well with higher erythrocyte sedimentation rate (ESR), B-symptoms and advanced-stage disease (P<0.05, P<0.05 and P<0.01, respectively). Expression of CD44 was significantly high in patients with HD and NHL who were in advanced stages of disease. High serum CD44 level was also associated with high tumor tissue expression of CD44 in patients with HD and BL. In addition, patients with higher levels of serum sCD44, had a poorer outcome and survival than those with lower sCD44 levels in HD and NHL groups. CONCLUSIONS: A high serum sCD44 level and/or tumor tissue expression at diagnosis is associated with poor prognostic criteria and/or unfavorable outcome in childhood leukemias and lymphomas.

Hereditary multiple exostoses and acute myeloid leukemia: an unusual association.

Hereditary multiple exostoses (HME) is an autosomal dominant disorder characterized by the presence of multiple exostoses. Three genetic loci have been identified, of which two (EXT1 and EXT2) have tumor suppressor activity. HME greatly increases the risk to develop sarcoma in the dysplastic tissue. The authors report an 8-year-old girl with HME who developed acute myeloblastic leukemia.

Hydroxychloroquine ototoxicity in a patient with rheumatoid arthritis.

We report a case of reversible sensorineural hearing loss due to hydroxychloroquine (HQ) treatment. The patient was a 34-year-old woman with 1 year of rheumatoid arthritis (RA). She developed reversible hearing loss after 5 months of HQ treatment. Sensorineural deafness has previously been reported with chloroquine treatment, but this is the first report of ototoxicity associated with HQ in RA.

Brucellosis transmitted by bone marrow transplantation.

We report a unique case of brucellosis transmitted by BMT. An 8-year-old boy with the diagnosis of Fanconi's anemia received an allogeneic BMT from his HLA-identical sibling. Routine culture from the infused marrow suspension grew Brucella abortus on day +4 post BMT. Spiking fevers occurred on days +2 and +16. The first febrile episode responded to broad-spectrum antibiotic therapy. However, the second episode did not. B. abortus was isolated from blood cultures taken during the second febrile episode. The Brucella agglutination titer was negative. Antibiotic therapy with oral doxycycline and i.v. gentamycin was successful with no recurrence of infection during 13 months of follow-up. The donor's blood culture was also positive for B. abortus and Brucella antibodies were detectable at 1:320 titer when he presented with fever and hepatosplenomegaly on day +32. We emphasize the need to consider brucellosis in patients undergoing BMT. We suggest that donor and recipient be evaluated for brucellosis especially in countries where the incidence of this infection is relatively high.

Natural killer cell numbers and cytotoxic activity in pediatric Hodgkin disease.

In this study peripheral blood natural killer (NK) cell activity was evaluated in 17 pediatric cases with Hodgkin disease (HD) (9 untreated, 8 in remission) and 20 age-matched healthy children. Peripheral blood CD16 and CD56 molecule expressions were also examined. No difference related to NK cell numbers and cytotoxic activity was detected at either stage of the disease. In cases in which long-term remission has been achieved (> or = 5 years) NK cell activity was slightly but not significantly increased in parallel with remission duration. Finally, no relation between NK cell activity and the etiology, prognosis, and severity of the disease has been established in children with HD.

Evaluation of the pancreas reserve in siblings of type I diabetic children.

INTRODUCTION: The purpose of this study was to determine the pancreas reserve in siblings of diabetic patients by screening islet cell antibodies (ICA), insulin auto antibodies (IAA), reduced C-peptide levels, first-phase insulin release and the derangement of cellular immunity (reduction of natural killer cells, abnormality of the T cell subpopulations). METHODS AND RESULTS: Twelve siblings (aged 9.3 +/- 2.8 years) of diabetic children were evaluated and results were compared with the control group (12.1 +/- 3.5 years). For siblings of the diabetic children, fasting, post-prandial and glucagon response C-peptide mean values were 2.2 +/- 1.2, 7.2 +/- 7.1 and 5.3 +/- 3.6 ng/mL, respectively, while in the control group they were 1.5 +/- 0.8, 3.6 +/- 2.0 and 5.1 +/- 2.9 ng/mL, respectively. There were no differences between the two groups. In 33%, postprandial C-peptide, and in 11% of the siblings, glucagon response C-peptide values were exaggerated. In siblings the first phase insulin release (FPIR) during an intravenous glucose tolerance test was 128.5 +/- 96.6 (above the 50th percentile) and stimulated insulin release (SIR) was 103.8 +/- 92.5 (above 25th percentile). Sibling values were significantly lower than the control group (FPIR 152.4 +/- 42.5, P = 0.01; SIR 134.9 +/- 38.2, P = 0.01). Values for FPIR (in two children) and SIR (three cases) were below the 5th percentile. In one, FPIR and SIR levels were both below the 1st percentile. Islet cell antibodies and IAA were also present in this subject. Treatment with nicotinamide was started in the cases with FPIR and SIR below the 5th percentile. We did not observe overt diabetic symptoms during the follow-up period of more than 3 years. CONCLUSION: We recommend that borderline insulin secretion be tested annually in siblings who show insufficient FPIR.

Serum levels and differential expression of intercellular adhesion molecule-1 in childhood leukemia and malignant lymphoma: prognostic importance and relationship with survival.

Serum levels and leukemic cell-tumor tissue expression of intracellular adhesion molecule-1 (ICAM-1/CD 54) were detected in 54 children with acute leukemia and malignant lymphoma. Serum samples were obtained from all patients before treatment and after cessation of the therapy from malignant lymphoma cases and during remission from leukemic patients. Twelve age-matched healthy children were included as a control group. The serum ICAM-1 levels were significantly higher in patients with acute lymphoblastic leukemia (ALL) or Hodgkin's disease (HD) than those in the control group (median values: 350.9, 286.4, and 138.4 ng/mL, respectively; P < .01 in each comparison). However, there were no significant differences concerning serum ICAM-1 levels between the control group and each of the acute myeloid leukemia (AML), non-Hodgkin's lymphoma (NHL), and Burkitt's lymphoma (BL) case groups (median values: 235.7, 222.7, 195.9, and 138.4 ng/mL, respectively; P > .05 in each comparison). Moreover, serum soluble ICAM-1 levels significantly declined in ALL or HD patients who were in complete remission (median values: 185.0 and 145.4 ng/mL, respectively; P < .05 in each comparison). In HD patients high levels of serum ICAM-1 could be correlated with high ESR (P < .01), whereas no statistically significant difference could be found when serum ICAM-1 titers were compared with stages, B symptoms, and histological subgroups, probably because of the inadequate number of patients in each group. Expression of ICAM-1 was mainly attributed to lymphocytes, vessels, and weakly to Hodgkin's cells, and this was significantly high in patients who were in advanced stages of disease. High serum sICAM-1 level was also associated with poor outcome and survival. Determination of serum level and/or tumor tissue expression of ICAM-1 in HD and ALL might represent an additional, but probably not independent, disease-associated marker to be used in the evaluation and/or monitoring of treatment response in patients with HD and ALL.

Changes with growth hormone treatment in growth hormone deficient children.

A total of 54 previously untreated patients (15 girls, 39 boys) with poor growth due to idiopathic growth hormone deficiency (IGHD) were treated with human growth hormone (hGH), continuously up to 4 years. All of the patients had a peak hGH level which was below 10 ng/mL after at least two pharmacological tests and/or blunted physiologic hGH secretion, and their height was below -2.5 s.d. for age and gender. After the 1st year of therapy, height velocity (HV) increased significantly when compared with baseline (from 3.18 +/- 0.76 cm/year to 9.17 +/- 1.03 cm/year; P < 0.001), declined during the 2nd year and then remained significantly higher than pretreatment HV. When considering improvement in height expressed by height standard deviation score (SDS), during the therapy all of the patients showed a significant gain +/- 1.72 +/- 1.09 (from -4.11 +/- 0.61 to -2.21 +/- 0.48). The height values were significantly higher than pretreatment, but remained below -2 s.d. after 4 years of hGH therapy in our patients. Increased height velocity has been sustained, but height improvement after therapy was inversely correlated to height SDS for chronological age of patients at the start of therapy. In conclusion post-treatment height has been shown to be related to height deficit at the beginning of therapy. Therapy was well tolerated with no local or systemic adverse effects or acceleration of bone age.