Successful treatment of neonatal respiratory failure caused by a novel surfactant protein C p.Cys121Gly mutation with hydroxychloroquine

SFTPC (surfactant protein C) mutations resulting in SP-C deficiency causing ongoing respiratory failure in the neonatal period represent a rare entity. We report a full-term female infant who developed respiratory distress and respiratory failure shortly after birth. From the first day of life the infant was mechanically ventilated. Application of exogenous surfactant or cortisone did not lead to any clinical improvement. Genetic analysis identified a novel SFTPC mutation as the cause of her lung disease. The patient was diagnosed as heterozygous for a p.Cys121Gly/C121G substitution encoded by exon 4, which could not be detected in both parents. Experimental therapy with hydroxychloroquine resulted in a significant clinical improvement within 2 weeks time. Mechanical ventilation was no longer needed, and the patient was discharged without additional oxygen demand. The patient remained well under therapy till the age of 6 months. After that time, the therapy was successfully discontinued.

Provoking allergens and treatment of anaphylaxis in children and adolescents--data from the anaphylaxis registry of German-speaking countries

Anaphylaxis is the most severe reaction of an IgE-mediated hypersensitivity. Data about affected patients may help to improve our knowledge of anaphylaxis and its medical care. We analysed data from the anaphylaxis registry of German speaking countries with regard to the provoking allergens and treatment modalities of anaphylaxis in children and adolescents. Inclusion criteria were severe systemic allergic reactions with concomitant pulmonary and/or cardiovascular symptoms. The data are collected by a password-controlled online-questionnaire. For this analysis, data of 197 reported anaphylactic reactions from children and adolescents registered between 2006 and 2009 were included. The data show that within the registered cases the most frequently affected organ systems for children and adolescents were the skin (89%) and the respiratory tract (87%) followed by symptoms of the cardiovascular system (47%) and the gastrointestinal tract (43%). The most frequent elicitors were food allergens accounting for 58% of cases, followed by insect venom (24%) and drugs (8%). The most frequent food allergens were peanuts followed by tree nuts and animal related food products. In 18% aggravating factors such as physical exercise were noted by the clinicians. 26% of the analysed patients had experienced more than one reaction. The data regarding the emergency treatment show that antihistamines (87%) and corticosteroids (85%) were often used but that adrenaline was rarely used (22% of the registered cases). Taken together these data show that the analysis of anaphylaxis by registration of affected individuals can provide data about provoking allergens and treatment measures but also suggest the impact of aggravating factors on anaphylactic reactions. The under-represented usage of adrenaline indicates the need of educational measures for patients and their physicians.

Association of coagulation-related and inflammation-related genes and factor VIIc levels with stroke: the Cardiovascular Health Study

BACKGROUND

Thrombosis and inflammation are critical in stroke etiology, but associations of coagulation and inflammation gene variants with stroke, and particularly factor VII levels, are inconclusive.

OBJECTIVES

To test the associations between 736 single-nucleotide polymorphisms (SNPs) between tagging haplotype patterns of 130 coagulation and inflammation genes, and stroke events, in the 5888 participants aged ≥ 65 years of the observational Cardiovascular Health Study cohort.

PATIENTS/METHODS

With 16 years of follow-up, age-adjusted and sex-adjusted Cox models were used to estimate associations of SNPs and FVIIc levels with future stroke.

RESULTS

Eight hundred and fifteen strokes occurred in 5255 genotyped participants without baseline stroke (748 ischemic strokes; 586 among whites). Among whites, six SNPs were associated with stroke, with a nominal P-value of < 0.01: rs6046 and rs3093261 (F7); rs4918851 and rs3781387 (HABP2); and rs3138055 (NFKB1A) and rs4648004 (NFKB1). Two of these SNPs were associated with FVIIc levels (units of percentage activity): rs6046 (β = -18.5, P = 2.38 × 10(-83)) and rs3093261 (β = 2.99, P = 3.93 × 10(-6)). After adjustment for age, sex, race, and cardiovascular risk factors, the association of FVIIc quintiles (Q) with stroke were as follows (hazard ratio; 95% confidence interval): Q1, reference; Q2, 1.4, 1.1-1.9); Q3, 1.1, 0.8-1.5); Q4, 1.5, 1.1-2.0); and Q5, 1.6, 1.2-2.2). Associations between SNPs and stroke were independent of FVIIc levels.

CONCLUSIONS

Variations in FVII-related genes and FVIIc levels were associated with risk of incident ischemic stroke in this elderly cohort, suggesting a potential causal role for FVII in stroke etiology.

Bayesian methods for meta-analysis of causal relationships estimated using genetic instrumental variables

Genetic markers can be used as instrumental variables, in an analogous way to randomization in a clinical trial, to estimate the causal relationship between a phenotype and an outcome variable. Our purpose is to extend the existing methods for such Mendelian randomization studies to the context of multiple genetic markers measured in multiple studies, based on the analysis of individual participant data. First, for a single genetic marker in one study, we show that the usual ratio of coefficients approach can be reformulated as a regression with heterogeneous error in the explanatory variable. This can be implemented using a Bayesian approach, which is next extended to include multiple genetic markers. We then propose a hierarchical model for undertaking a meta-analysis of multiple studies, in which it is not necessary that the same genetic markers are measured in each study. This provides an overall estimate of the causal relationship between the phenotype and the outcome, and an assessment of its heterogeneity across studies. As an example, we estimate the causal relationship of blood concentrations of C-reactive protein on fibrinogen levels using data from 11 studies. These methods provide a flexible framework for efficient estimation of causal relationships derived from multiple studies. Issues discussed include weak instrument bias, analysis of binary outcome data such as disease risk, missing genetic data, and the use of haplotypes.

[Primary ciliary dyskinesia causing neonatal respiratory distress]

BACKGROUND

Primary ciliary dyskinesia (PCD) is a hereditary disorder of structure and function of the cilia of respiratory epithelium of the upper and lower airways. Prevalence is estimated with 1:15 000 to 1:30 000 births. We present a newborn infant with respiratory distress caused by PCD.

PATIENT

On the first day of life, the male newborn developed dyspnoe and cyanosis, so that CPAP and short term ventilation was necessary. Varying atelectasis impressed on the chest radiographs and the diagnosis of PCD was made by nasal brush biopsies. Causative is a lack of the inner dynein arms of the cilia. The clinical features of newborns with the diagnoses of PCD are listed and compared with the own case.

CONCLUSION

PCD is a rare cause of neonatal respiratory distress and should be considered in term infants with unknown and prolonged course even if Situs inversus is lacking.

Putative Aspergillus niger-induced oxalate nephrosis in sheep

A sheep farmer provided a maize-based brewer's grain (mieliemaroek) and bales of Eragrostis curvula hay to ewes and their lambs, kept on zero-grazing in pens. The 'mieliemaroek' was visibly mouldy. After 14 days in the feedlot, clinical signs, including generalised weakness, ataxia of the hind limbs, tremors and recumbency, were noticed. Six ewes died within a period of 7 days. A post mortem examination was performed on 1 ewe. The carcass appeared to be cachectic with mild effusions into the body cavities; mild lung congestion and pallor of the kidneys were observed. Microscopical evaluation revealed nephrosis and birefringent oxalate crystals in the renal tubules when viewed under polarised light. A provisional diagnosis of oxalate nephrosis with subsequent kidney failure was made. Amongst other fungi, Aspergillus niger was isolated from 'mieliemaroek' samples submitted for fungal culture and identification. As A. niger is known to synthesise oxalates, a qualitative screen to detect oxalic acid in the mieliemaroek and purified A. niger isolates was performed using high-performance liquid chromatography (HPLC). Oxalic acid was detected, which supported a diagnosis of soluble oxalate-induced nephropathy.

Questionnaire-based survey of lifetime-prevalence and character of allergic drug reactions in German children

Data on the epidemiology of adverse drug reactions (ADR), especially allergic drug reactions, in children are rare. The reported prevalence of ADR in pediatric populations varies a lot, depending on type of the study and the country where the data were collected. In order to assess the prevalence of ADR and allergic drug reactions in a population of German children, we conducted a study in a German pediatric university hospital. A questionnaire concerning occurrence and character of ADR was distributed to all parents presenting their children in the hospital for planned admissions or in the emergency department from May 2004 to November 2004. Additional telephone interviews were conducted to specify the reported symptoms in ambiguous cases. One thousand four hundred forty-seven questionnaires were collected. The reported life-time prevalence of ADR according to the information given by the parents was 7.5% (108/1447). Six of the reactions were severe, three children had experienced anaphylactic reactions. In 4.2% (61/1447), the history was suspicious for a potential allergic mechanism because of an immediate or late phase cutaneous drug reaction. In this group, the suspected drugs were antibiotics in 85% (32.7% aminopenicillins, 29.5% other penicillins, 11.5% cefaclor, 8.2% macrolides and 18% others), antiphlogistic and respiratory drugs in 4.9% each and vaccines and contrast media in 3.3% each. There was a higher percentage of children under the age of four suffering from ADR. This trend was not significant when analyzing only the allergic reactions. Forty-four percent of the parents stated, their children suffer from drug allergy, although a clear non-allergic reaction was described. Both, ADR and allergic drug reactions are frequent phenomena in children. It is important to monitor drug therapy for any adverse reaction in order to inform the parents about the character of the adverse reaction, the necessary consequences and to initiate further diagnostic procedures.

Congenital heart disease and other heterotaxic defects in a large cohort of patients with primary ciliary dyskinesia

BACKGROUND

Primary ciliary dyskinesia (PCD) is a recessive genetic disorder that is characterized by sinopulmonary disease and reflects abnormal ciliary structure and function. Situs inversus totalis occurs in approximately 50% of PCD patients (Kartagener's syndrome in PCD), and there are a few reports of PCD with heterotaxy (situs ambiguus), such as cardiovascular anomalies. Advances in diagnosis of PCD, such as genetic testing, allow the systematic investigation of this association.

METHODS AND RESULTS

The prevalence of heterotaxic defects was determined in 337 PCD patients by retrospective review of radiographic and ultrasound data. Situs solitus (normal situs) and situs inversus totalis were identified in 46.0% and 47.7% of patients, respectively, and 6.3% (21 patients) had heterotaxy. As compared with patients with situs solitus, those with situs abnormalities had more ciliary outer dynein arm defects, fewer inner dynein arm and central apparatus defects (P<0.001), and more mutations in ciliary outer dynein arm genes (DNAI1 and DNAH5; P=0.022). Seven of 12 patients with heterotaxy who were genotyped had mutations in DNAI1 or DNAH5. Twelve patients with heterotaxy had cardiac and/or vascular abnormalities, and most (8 of 12 patients) had complex congenital heart disease.

CONCLUSIONS

At least 6.3% of patients with PCD have heterotaxy, and most of those have cardiovascular abnormalities. The prevalence of congenital heart disease with heterotaxy is 200-fold higher in PCD than in the general population (1:50 versus 1:10 000); thus, patients with PCD should have cardiac evaluation. Conversely, mutations in genes that adversely affect both respiratory and embryological nodal cilia are a significant cause of heterotaxy and congenital heart disease, and screening for PCD is indicated in those patients.