Analysis of chromosomal aberrations and γH2A.X foci to identify radiation-sensitive ataxia-telangiectasia patients.

Ataxia-telangiectasia (AT) is a rare inherited recessive disorder which is caused by a mutated Ataxia-telangiectasia mutated (ATM) gene. Hallmarks include chromosomal instability, cancer predisposition and increased sensitivity to ionizing radiation. The ATM protein plays an important role in signaling of DNA double-strand breaks (DSB), thereby phosphorylating the histone H2A.X. Non-functional ATM protein leads to defects in DNA damage response, unresolved DSBs and genomic instability. The aim of this study was to evaluate chromosomal aberrations and γH2A.X foci as potential radiation sensitivity biomarkers in AT patients. For this purpose, lymphocytes of 8 AT patients and 10 healthy controls were irradiated and induced DNA damage and DNA repair capacity were detected by the accumulation of γH2A.X foci. The results were heterogeneous among AT patients. Evaluation revealed 2 AT patients with similar γH2A.X foci numbers as controls after 1 h while 3 patients showed a lower induction. In regard to DNA repair, 3 of 5 AT patients showed poor damage repair. Therefore, DNA damage induction and DNA repair as detected by H2A.X phosphorylation revealed individual differences, seems to depend on the underlying individual mutation and thus appears not well suited as a biomarker for radiation sensitivity. In addition, chromosomal aberrations were analyzed by mFISH. An increased frequency of spontaneous chromosomal breakage was characteristic for AT cells. After irradiation, significantly increased rates for non-exchange aberrations, translocations, complex aberrations and dicentric chromosomes were observed in AT patients compared to controls. The results of this study suggested, that complex aberrations and dicentric chromosomes might be a reliable biomarker for radiation sensitivity in AT patients, while non-exchange aberrations and translocations identified both, spontaneous and radiation-induced chromosomal instability.

The Duesseldorf warning signs for primary immunodeficiency: is it time to change the rules?

OBJECTIVE: Different sets of warning signs can be used if primary immunodeficiency (PID) is suspected: those of the Jeffrey Modell Foundation (JMF), the German Patients' Organisation for Primary Immunodeficiencies (DSAI) and the Association of the Scientific Medical Societies in Germany (AWMF). A few studies have tested the JMF criteria, with unconvincing results, but the diagnostic models of the DSAI and AWMF have not been tested at all. We set out to establish the utility of these three scoring systems and compare them with our own set of five warning signs (Duesseldorf criteria). DESIGN: Prospective study. PATIENTS: Two hundred ten patients admitted to our hospital between 2010 and 2012 with suspected PID. RESULTS: PID were found in 36 (17 %) of the patients admitted. Of the established sets of warning signs, the JMF and the DSAI had inadequate sensitivity, while the DSAI and the AWMF showed insufficient specificity. Our own criteria were analyzed with regard to maximal specificity and sensitivity (Youden Index) and sensitivity and yielded NPV of 0.89 and 0.91 respectively. Youden index revealed combination of five signs and symptoms: lymphopenia, otitis media >7, failure to thrive, failure to grow normally, pneumonia >1. For maximum negative predictive value the following set was found: lymphopenia, hypogammglobulinemia, failure to thrive, growth disorders, iv antibiotics and abscesses. CONCLUSION: In contrast to the new, evaluated Duesseldorf criteria, all three established sets of warning signs proved inadequate for preselection of patients for admission to specialized PID centers. The Duesseldorf criteria should now being tested in further studies.

Agammaglobulinemia and lack of immunization protection in exudative atopic dermatitis.

UNLABELLED: Atopic dermatitis is very frequent in the first 6 months of life, and the severe exudative form of this skin disorder is by no means rare. Failure to achieve immunization protection is a potentially life-threatening complication of exudative atopic dermatitis that may go unrecognized. We report the case of a 6-month-old infant with severe exudative atopic dermatitis in whom hypoproteinemia and agammaglobulinemia were attributed to the massive exudation after exclusion of other possible causes. The patient failed to respond to standard immunization, and adequate protection with a good antibody response could be achieved only after exudation from the skin lesions had been treated by intensive topical skin therapy and multiple intravenous immunoglobulin substitution. Two otherwise similar earlier case reports did not investigate the immune status. Therefore, to the best of our knowledge, this is the first report to draw attention to absence of immunization protection in exudative atopic dermatitis. CONCLUSION: We hope that our case report will motivate pediatricians to check the immunization status of patients with exudative atopic dermatitis and take the necessary steps to improve their care.

COL2A1 mutation as a cause of premature osteoarthritis in a 13-year-old child.

Diagnostic assessment of osteoarthritis in children and adolescents is difficult. Here, we report the sixth family with a COL2A1 mutation R275C. The index patient, her mother and her three brothers had severe coxarthrosis, in some cases requiring surgery. Only the mother was hard of hearing, and only her children had brachydactyly of the fourth digit. The index patient suffered a femoral neck fracture after minor trauma at a time when osteoarthritis was not yet radiologically detectable. Hip fracture or osteoarthritis of unclear origin in childhood should prompt genetic work-up for the purposes of correct classification and genetic counseling.

Association of nephrotic syndrome with immune reconstitution inflammatory syndrome.

BACKGROUND: Up to 50% of patients with severe immune deficiency experience an excessive inflammatory response called immune reconstitution inflammatory syndrome (IRIS) after the initiation of antiretroviral therapy (ART). IRIS has been observed after various opportunistic infections with pathogens such as mycobacteria, including Bacille Calmette-Guérin, cryptococci, human herpesvirus-8, non-Hodgkin's lymphoma, and progressive multifocal leukoencephalopathy. Non-acquired immune deficiency-defining illnesses can also deteriorate after commencement of ART. Renal IRIS has been reported in a few patients with mycobacterial infections, but to the best of our knowledge no cases of nephrotic syndrome and IRIS have been described. CASE-DIAGNOSIS/TREATMENT: We report the case of an infant with human immunodeficiency virus-1 (HIV-1) infection, Pneumocystis pneumonia, and encephalopathy. During immune reconstitution the patient developed nephrotic syndrome. Treatment of nephrotic syndrome was initiated with prednisone, an angiotensin-converting enzyme inhibitor (lisinopril), and low-molecular-weight heparin. ART was continued, but only a low level of lopinavir/ritonavir could be achieved. There was no relapse of nephrotic syndrome during 10 months of follow-up. CONCLUSIONS: Nephrotic syndrome may occur in infants during immune reconstitution and should not be overlooked.

Primary necrotizing lymphocytic central nervous system vasculitis due to perforin deficiency in a four-year-old girl.

We report the case of a 4-year-old girl who presented with headaches, ataxia, and visual disturbances. Cranial magnetic resonance imaging showed multiple supra- and infratentorial lesions with peripheral contrast enhancement and central necrosis. Brain biopsy revealed necrotizing lymphocytic vasculitis of undetermined etiology. Perforin expression was found to be significantly reduced in the patient's peripheral blood cells, and sequence analysis of the patient's perforin gene showed a compound heterozygous state with 1 nonsense mutation and 2 missense alterations in exon 2. Central nervous system (CNS) vasculitis was thus attributed to the perforin deficiency, and the patient was successfully treated by transplantation of stem cells from an HLA-identical brother. The findings described herein indicate that, even in the absence of classic non-neurologic symptoms of hemophagocytic lymphohistiocytosis, measurement of perforin expression should be one of the diagnostic tests used to identify the cause of unexplained CNS vasculitis, since this may have profound implications regarding therapy.

Recommendations for the use of methotrexate in juvenile idiopathic arthritis.

Juvenile idiopathic arthritis (JIA) is one of the most common rheumatic diseases in childhood. In a significant number of JIA cases the disease is resistant to therapy with NSAIDs, intra-articular corticosteroid injections, and physiotherapy, and methotrexate is used as a second-line agent. The efficacy of methotrexate therapy in children with JIA has been demonstrated in prospective controlled trials and this agent appears to have slightly superior efficacy compared with leflunomide. Data from randomized studies indicate a starting dose of 10-15 mg/m(2)/week orally. The dose of parenteral methotrexate can be increased to 15-20 mg/m(2)/week. Combination therapy with methotrexate and an NSAID is recommended. However, there are still no data on when to initiate methotrexate in JIA and how long children should be treated. The most common adverse effects are aversion to the drug and nausea. In the case of minor adverse effects the use of folic acid at a dosage of 1 mg/day is feasible. In JIA, daily folate supplementation has only been studied in one small heterogeneous cohort with a very short observation period and, at present, a general recommendation on daily folate supplementation cannot be made. In summary, methotrexate is seen by many pediatric rheumatologists as the first-choice, second-line drug; there is good evidence of its efficacy in JIA. However, in light of the recent introduction of biologic agents, the place of methotrexate in the treatment of JIA may have to be redefined in the coming years.

Hypercalcemia with nephrocalcinosis and impaired renal function due to increased Parathyroid hormone secretion at onset of childhood acute lymphoblastic leukemia.

The present case report contributes new aspects to the etiology and the appearance of hypercalcemia at the onset of childhood acute lymphoblastic leukemia [ALL]. Malignancy associated hypercalcemia is often associated with an increase of Parathyroid hormone-related protein [PTHrP]. In our case PTHrP was normal but high levels of Parathormon [PTH] were measured. This increase of PTH was not due to hyperparathyroidism nor was it due to osteolytic lesions or metabolic disease interfering with bone density. The most likely explanation for high PTH levels in our case was that PTH was secreted by leukemic blasts and thus responsible for hypercalcemia. Uncommonly, hypercalcemia was clinically associated with moderate renal impairment and marked nephrocalcinosis.