Search for a genetic cause in children with unilateral isolated microtia and congenital aural atresia.

PURPOSE: Microtia describes a spectrum of auricular malformations ranging from mild dysplasia to anotia. A vast majority of microtia patients demonstrate congenital aural atresia (CAA). Isolated microtia has a right ear predominance (58-61%) and is more common in the male sex. Isolated microtia is a multifactorial condition involving genetic and environmental causes. The aim of this study is to describe the phenotype of children with unilateral isolated microtia and CAA, and to search for a common genetic cause trough DNA analysis. METHODS: Phenotyping included a complete clinical examination. Description on the degree of auricular malformation (Weerda classification-Weerda 1988), assessment for hemifacial microsomia and age-appropriate audiometric testing were documented. Computerized tomography of the temporal bone with 3-D rendering provided a histopathological classification (HEAR classification-Declau et al. 1999). Genetic testing was carried out by single nucleotide polymorphism (SNP) microarray. RESULTS: Complete data are available for 44 children (50% was younger than 33 days at presentation; 59.1% boys; 72.7% right ear). Type III microtia was present in 28 patients. Type 2b CAA existed in 32 patients. All patients had a normal hearing at the non-affected side. Genome wide deletion duplication analysis using microarray did not reveal any pathological copy number variant (CNV) that could explain the phenotype. CONCLUSIONS: Type III microtia (peanut-shell type) in combination with a type 2b CAA was the most common phenotype, present in 23 of 44 (52.3%) patients with isolated unilateral microtia. No abnormalities could be found by copy number variant (CNV) analysis. Whole exome sequencing in a larger sample with a similar phenotype may represent a future diagnostic approach.

Disclosure pattern and follow-up after the molecular diagnosis of BRCA/CHEK2 mutations.

Five to 10% of all breast cancer cases are due to mutations of high penetrance susceptibility genes, especially BRCA1 and BRCA2. In families with known BRCA mutations, disclosure of genetic test results could induce relatives to undergo genetic testing themselves and adopt cancer risk management strategies, if necessary. This study examines disclosure patterns of individuals tested for mutations in the BRCA1, BRCA2 and CHEK2 genes to first-degree relatives with emphasis on a possible gender difference. It also assesses which management strategy is preferred by mutation-positive women in Belgium and the influence of psychological characteristics on communication and choice of management strategy. Ninety-nine adults from BRCA/CHEK2 families, selected from the Centre of Medical Genetics of Antwerp, were included in the study. They were provided with medical and psychological questionnaires, the latter being the Self-Assessment Questionnaire, which is the Dutch version of the Spielberger State-Trait Anxiety Inventory and the Dutch version of the Coping Inventory for Stressful Situations (CISS-NL). The survey focused on disclosure, coping and management strategies with special attention on possible gender differences. The influence of socio-demographic and medical data on disclosure and cancer risk management as well as the influence of psychological features were examined by means of various statistical analyses. Ninety-nine patients were included, of whom 25 (25 %) were male. Eighty-seven percent of the participants informed all of their adult first-degree relatives about their mutation status without any gender discrimination. Seventy-eight percent of highly-educated participants informed all of their adult first-degree relatives, compared to 98 % of less formally-educated participants (p = 0.006). The majority of mutation-positive women preferred prophylactic surgery to surveillance. Psychological differences appeared to have little influence on disclosure patterns and management strategies. The gender difference seems to be less pronounced than previously assumed. A striking observation, however, is the fact that significantly more participants who were less formally-educated informed all of their adult first-degree relatives, compared to participants who were highly-educated. In our study population, most female mutation carriers opted for prophylactic surgery. Since the study population is small, further studies are needed to enhance the generalizability of these results.

Auditory neuropathy: a challenge for diagnosis and treatment.

In current terminology, auditory neuropathy spectrum disorder (ANSD) is a disease involving the disruption of the temporal coding of acoustic signals in auditory nerve fibres, resulting in the impairment of auditory perceptions that rely on temporal cues. There is debate about almost every aspect of the disorder, including aetiology, lesion sites, and the terminology used to describe it. ANSD is a heterogeneous disease despite similar audiological findings. The absence of an auditory brainstem response (ABR) and the presence of otoacoustic emissions (OAE) suggest an ANSD profile. However, to determine the exact anatomical site of the disorder, more in-depth audiological and electrophysiological tests must be combined with imaging, genetics and neurological examinations. Greater diagnostic specificity is therefore needed to provide these patients with more adequate treatment.

Evaluation of RAD51C as cancer susceptibility gene in a large breast-ovarian cancer patient population referred for genetic testing.

Despite extensive analysis of the BRCA1 and BRCA2 genes, germline mutations are detected in <20% of families with a presumed genetic predisposition for breast and ovarian cancer. Recent literature reported RAD51C as a new breast cancer susceptibility gene. In this study, we report the analysis of 410 patients from 351 unrelated pedigrees. All were referred for genetic testing and we selected families with at least one reported case of ovarian cancer in which BRCA1&2 mutations were previously ruled out. We analyzed the coding exons, intron-exons boundaries, and UTRs of RAD51C. Our mutation analysis did not reveal any unequivocal deleterious mutation. In total 12 unique sequence variations were identified of which two were novel. Our study and others suggest a low prevalence of RAD51C mutations with an exception for some founder populations. This observation is in favor of the rare allele hypothesis in the debate over the nature of the genetic contribution to individual susceptibility to breast and ovarian cancer and further genome-wide studies in high risk families are warranted.

Molecular diagnostics of intestinal parasites in returning travellers.

A new diagnostic strategy was assessed for the routine diagnosis of intestinal parasites in returning travellers and immigrants. Over a period of 13 months, unpreserved stool samples, patient characteristics and clinical data were collected from those attending a travel clinic. Stool samples were analysed on a daily basis by microscopic examination and antigen detection (i.e. care as usual), and compared with a weekly performed multiplex real-time polymerase chain reaction (PCR) analysis on Entamoeba histolytica, Giardia lamblia, Cryptosporidium and Strongyloides stercoralis. Microscopy and antigen assays of 2,591 stool samples showed E. histolytica, G. lamblia, Cryptosporidium and S. stercoralis in 0.3, 4.7, 0.5 and 0.1% of the cases, respectively. These detection rates were increased using real-time PCR to 0.5, 6.0, 1.3 and 0.8%, respectively. The prevalence of ten additional pathogenic parasite species identified with microscopy was, at most, 0.5%. A pre-selective decision tree based on travel history or gastro-intestinal complaints could not be made. With increased detection rates at a lower workload and the potential to extend with additional parasite targets combined with fully automated DNA isolation, molecular high-throughput screening could eventually replace microscopy to a large extent.

Time delays in diagnosis of pulmonary tuberculosis: a systematic review of literature.

BACKGROUND: Delay in diagnosis of pulmonary tuberculosis results in increasing severity, mortality and transmission. Various investigators have reported about delays in diagnosis of tuberculosis. We aimed at summarizing the data on these delays in diagnosis of tuberculosis. METHODS: A systematic review of literature was carried out. Literature search was done in Medline and EMBASE from 1990 to 2008. We used the following search terms: delay, tuberculosis, diagnosis, and help-seeking/health-seeking behavior without language restrictions. In addition, indices of four major tuberculosis journals were hand-searched. Subject experts in tuberculosis and authors of primary studies were contacted. Reference lists, review articles and text book chapters were also searched. All the studies were assessed for methodological quality. Only studies carried out on smear/culture-positive tuberculosis patients and reporting about total, patient and health-care system delays were included. RESULTS: A total of 419 potential studies were identified by the search. Fifty two studies qualified for the review. The reported ranges of average (median or mean) total delay, patient delay, health system delay were 25-185 days, 4.9-162 days and 2-87 days respectively for both low and high income countries. Average patient delay was similar to health system delay (28.7 versus 25 days). Both patient delay and health system delay in low income countries (31.7 days and 28.5 days) were similar to those reported in high income countries (25.8 days and 21.5 days). CONCLUSION: The results of this review suggest that there is a need for revising case-finding strategies. The reported high treatment success rate of directly observed treatment may be supplemented by measures to shorten the delay in diagnosis. This may result in reduction of infectious cases and better tuberculosis control.

Risk factors for delay in the diagnosis and treatment of tuberculosis at a referral hospital in Rwanda.

SETTING: Kigali University Hospital, the main referral centre for TB in Rwanda. OBJECTIVE: To evaluate delays in the diagnosis and treatment of tuberculosis (TB) and associated risk factors. DESIGN: Prospective data collection of patients treated for pulmonary TB (PTB) or extra-pulmonary TB (EPTB) between June and September 2006. RESULTS: Of 104 patients with a mean age of 35 years (range 17-84) recruited into the study, 62% were HIV-positive. EPTB was diagnosed in 60 cases. The median total, health care and patient delays were respectively 57, 28 and 25 days. The health system delay before referral was significantly longer than the delay at our institution (18 vs. 6 days, P<0.0001). Risk factors for a longer health system delay at our institution were smear-negative PTB or EPTB (OR 5.12) and a trial of antibiotics (OR 2.96). The latter was also found to significantly prolong total delay (OR 2.85), as did rural residence (OR 4.86). No significant association was found between patient delay and age, sex, profession or health insurance status. CONCLUSION: Smear-negative PTB and EPTB were associated with longer health system delays. A trial of antibiotics significantly increased the health system delay. Its use, recommended by the World Health Organization in case of smear-negative TB and EPTB in developing countries, needs validation at the tertiary health care level.

Case report: "auditory neuropathy" in a newborn caused by a cerebellopontine angle arachnoid cyst.

We present a 6-week-old girl, referred because of failed newborn hearing screening in the right ear. Click-evoked oto-acoustic emissions were present in both ears, auditory brainstem responses (ABR) were present in the left but totally absent in the right ear. A magnetic resonance imaging (MRI) study revealed a large arachnoid cyst in the right cerebellopontine angle (CPA) and a diagnosis of "auditory neuropathy/auditory dyssynchrony" was established. A microsurgical resection of the cyst wall and fenestration was performed by a retro sigmoid approach. This is the first case in the literature of auditory neuropathy (AN) in an infant caused by a cerebellopontine angle arachnoid cyst.

The facio-audio-symphalangism syndrome in a four generation family with a nonsense mutation in the NOG-gene.

We report a four generation family with features of the facio-audio-symphalangism syndrome. This condition is characterized by proximal symphalangism, conductive hearing loss due to stapes fixation and a distinctive facies. A novel nonsense mutation in the NOG gene on chromosome 17q22 was identified in the patients. The variable expression and progressive nature of the syndrome is well illustrated by this family. The role of Noggin as the causative factor of symphalangism is discussed.

Clinical and genetic significance of unilateral Lisch nodules.

PURPOSE: Bilateral Lisch nodules are highly characteristic for neurofibromatosis type 1 (NF1). We wished to study the clinical and genetic implications of unilateral Lisch nodules. METHODS: Retrospective study of the clinical data of 59 patients who received genetic counselling for neurofibromatosis type 1 (NF1) or type 2 (NF2) and were examined at the department of ophthalmology. RESULTS: Unilateral Lisch nodules were observed in 4 cases: one child with NF1 initially presented unilateral Lisch nodules but developed bilateral Lisch nodules by the age of 9. In 2 cases segmental NF1 was the most probable diagnosis and in one case isolated Lisch nodules were observed. Of the 35 NF1 patients 28 ultimately developed bilateral Lisch nodules. Seven NF1 patients did not demonstrate the nodules. At follow-up no Lisch nodules were detected in 2 neurofibromatosis type 2 patients, in 4 patients in whom the diagnosis of NF1 remained doubtful and in 15 patients without NF1. CONCLUSION: Because isolated Lisch nodules are very rare, their presence warrants a thorough patient history and clinical examination to either confirm or exclude generalised or segmental neurofibromatosis type 1.

Evaluation of two staging systems for HIV infection for use in developing countries.

OBJECTIVE: To evaluate the clinical axis of the World Health Organization (WHO) clinical staging system and the modified WHO staging system proposed by Montaner et al. using the lymphocyte strata > 1500, 1500-1000 and < 1000 cells x 10(6)/l. DESIGN: Cross-sectional study. PATIENTS: Four hundred and fifteen consecutive patients with HIV infection attending three HIV reference centres in Belgium. METHODS: Absolute CD4 lymphocyte counts were compared between stages within the two staging systems. RESULTS: Median CD4 lymphocyte counts decreased with increasing stage of disease in both staging systems. Differences in median CD4 lymphocyte counts between stages of each staging system were statistically significant (Kruskal-Wallis one-way analysis of variance, P < 0.001). The WHO clinical stage 1 and the modified WHO stage I had positive predictive values of 56 and 58%, respectively, for identifying patients with CD4 lymphocyte levels > 500 cells x 10(6)/l. The WHO clinical stage 4 and the modified WHO stage IV had positive predictive values of 79 and 80%, respectively, for identifying patients with CD4 lymphocyte levels < 200 cells x 10(6)/l. CONCLUSIONS: The WHO clinical staging system or a modified version of this system using lymphocytes stratification may be a good alternative in developing countries to the CD4 lymphocyte count-based HIV staging system used in the developed world. Cohort studies in developing countries are needed to assess their prognostic value.

PIP: In 1990, Belgium, physicians enrolled 415 consecutive patients attending HIV reference centers in Antwerp, Brussels, and Ghent in a cross-sectional study designed to evaluate the clinical axis of the WHO staging system with and without the lymphocyte stratification proposed by Montaner el al. (that is, modified WHO staging system) (1500, 1500- 1000, and 1000 cells x 1 million/l). They filled in a standardized questionnaire with all criteria of the WHO staging system. Laboratory personnel used standard hematology and flow cytometry techniques to determine absolute and CD4 lymphocyte counts. 80% of the patients were Caucasians. 46% of all patients were homosexual and 42% were heterosexual; 79.2% were men. Median CD4 lymphocyte counts fell in both staging systems as the stage of HIV infection increased. There were significant differences in median CD4 counts between stages of each staging system (p .001). The modified WHO staging system's stage I was more sensitive at identifying patients with CD4 lymphocyte counts of more than 500 cells x 1 million/l than the WHO clinical stage 1 (83% sensitivity vs. 48% sensitivity). The positive predictive value of WHO clinical stage 4 and of the modified WHO staging system's stage IV for identifying people with CD4 lymphocyte counts of less than 200 cells x 1 million/l was quite high (79% and 80%, respectively). The researchers suggested that clinicians use stages 4 and IV as end-points is clinical trials in developing countries. Clinicians completing the questionnaire knew the patients' earlier CD4 lymphocyte count, which may have introduced a bias in the study. For example, they may have more thoroughly examined patients with low CD4 lymphocyte counts than those with normal counts. Nevertheless, the study's results indicated that either one of these systems may be a good alternative in developing countries to the technical equipment-dependent CD4 lymphocyte count-based HIV staging system used in developed countries. Cohort studies in developing countries would evaluate their prognostic value.

Sporadic, idiopathic MCA syndrome with mandibulofacial dysostosis and tibial hemimelia.

We report on a Brazilian woman with mandibulofacial dysostosis, cleft lip/palate, vertebral anomalies, abnormally modeled femora, and bilateral tibial agenesis. The clinical aspects involving this patient strongly suggest an unreported condition. Clinical and genetic aspects are discussed.

Oculo-auriculo-vertebral complex and uncommon associated anomalies: report on 8 unrelated Brazilian patients.

We report on 8 Brazilian patients with the oculo-auriculo-vertebral (OAV) complex with associated uncommon anomalies of hydrocephalus, porencephalic cyst, hand abnormalities, terminal/paraxial hemimelia, Klippel-Feil anomaly, Rokitansky sequence, fibrous dysplasia, and dextrocardia. Our patients show that in some instances a definite diagnosis can be difficult within the wide clinical picture of the OAV complex.

Marden-Walker-like syndrome without psychomotor retardation: report of a Brazilian girl born to consanguineous parents.

We report on a Brazilian girl, born to consanguineous parents and presenting a multiple congenital anomaly (MCA) syndrome, mainly characterized by blepharophimosis, cleft palate, and arachnodactyly. The clinical aspects involving this patient suggest an apparently undescribed "new" autosomal recessive syndrome.

The prevalence and transmission of hepatitis B virus infection in urban, rural and institutionalized black children of Natal/KwaZulu, South Africa.

The sera of statistically selected urban (805), rural (238) and institutionalized (127) black children were tested for markers of hepatitis B virus (HBV) infection. The age-standardized (6-14 years) prevalence rates of HBs antigenaemia for comparison between urban, rural and institutionalized children were 10%, 18.5% and 25.1% and the HBV exposure rates were 31.4%, 62.1% and 72.0% respectively. In the newborn to six years age group the prevalence rates of HBsAg and HBV exposure were 2.5% and 7.1% for urban children and 53.1% and 70.3% for institutionalized children. Peak prevalences of HBsAg occurred in the 6-8 year age group and were 14.4% and 22.6% in urban and rural children respectively. Hepatitis Be Antigen (HBeAg) was detected in 46.5% and antibodies to hepatitis Be antigen (HBeAb) in 10.0% of all HBsAg positive children. Multiple mechanisms involving horizontal rather than vertical transmission appeared to be important in urban children, with HBV exposure in females being significantly associated with ear-piercing (p less than 0.001) and scarification (p less than 0.05). In addition, HBsAg was detected in 25 of 29 pools of bloodfed mosquitoes caught at the children's institution and was negative in all four pools of unfed mosquitoes, suggesting that these arthropods may also be one factor in the horizontal spread of HBV infection. Familial clustering of HBV infection was suggested by a significantly higher (p less than 0.01) prevalence of HBsAg amongst family contacts of HBsAg positive urban children (17.7%) than in the control groups of family contacts of HBsAb positive children (8%) and children who were negative for all HBV markers (2.4%). The significance and implications of these findings are discussed.

Cholecystojejunocholecystostomy: a new method of biliary drainage in auxiliary liver allotransplantation.

A subhepatic, whole auxiliary liver allotransplant technique, previously developed in the pig, was assessed for technical feasibility in 26 human cadaver transplants. All technical aspects of the subhepatic technique were feasible, with the exception of donor to recipient gallbladder-to-gallbladder anastomosis, which could only be performed in 50% of subjects due to excessive separation of the two gallbladders. To oversome the problem, an original technique was developed--namely, the use of an isolated, vascularized, isoperistaltic loop of jejunum to act as a conduit between donor and recipient gallbladders (cholecystojejunocholecystostomy). Cholecystojejunocholecystostomy was subsequently developed and studied in a series of live porcine auxiliary allografts. The local, reginal, and general effects seen in 14 allografted pigs with cholecystojejunocholecystostomy were compared with those seen in a parallel and identical series of 14 allografts with cholecystocholecystostomy. The subhepatic transplantation technique is described in detail for the first time. Liver biopsies, blood samples, and clinical data were obtained at weekly intervals and at 28 days all survivors were killed. Cholecystojejunocholecystostomy proved to be a successful method of biliary drainage in the pig. Thirteen of the 14 interposed jejunal loops were viable and essentially normal at autopsy, leaks and naked eye stasis were infrequent, and the histological incidence of intrahepatic cholangitis and cholestasis minimal. The local, regional, and general effects were comparable in every way with those obtained with cholecystocholecystostomy.

Evaluation of two tests based on the detection of histidine rich protein 2 for the diagnosis of imported Plasmodium falciparum malaria.

The ParaSight-F dipstick test (Becton Dickinson, USA) and the ICT Malaria Pf test (ICT, Australia) both detect histidine rich protein 2 (HRP-2), a water-soluble antigen expressed by Plasmodium falciparum trophozoites. The present study compared the diagnostic performance of both tests in persons returning to Belgium from countries endemic for malaria. During a period of 18 months both tests were performed on all patients returning from the tropics with a positive malaria blood film. Patients with fever without an obvious cause were used as controls. For the ParaSight-F test, considering P. falciparum trophozoites only, sensitivity was 95% and specificity 90%. Considering trophozoites of all species of Plasmodium, sensitivity was 71% and specificity 87%. Finally, considering patients with clinical malaria, the sensitivity of the test was 72% and specificity 87%. For the ICT Malaria Pf test, sensitivity was 95% and specificity 89% for P. falciparum trophozoites only, 71% and 86% for trophozoites of all species, and 72% and 87% for clinical malaria. Both tests gave highly comparable results. However, antigen detection assays cannot replace conventional microscopy in diagnosing imported malaria. Thick blood film examination is more sensitive and more specific, it allows estimation of parasitaemia and distinction between parasite growth stages, and it covers all species. Moreover, with treated patients the use of antigen tests might lead to problems in determining the efficacy of therapy.

Treatment failure of a single high dose of ivermectin for Mansonella perstans filariasis.

Infections with Mansonella perstans are common in certain parts of Africa and South America. There is no standard treatment at present. We evaluated the effect of a single high dose of ivermectin (600 micrograms/kg) on microfilaraemia in 7 consecutive patients. No decrease in microfilarial counts could be demonstrated after a follow-up period of 7-56 d.