Monogenic diabetes in adults: A multi-ancestry study reveals strong disparities in diagnosis rates and clinical presentation

AIM

Identification of monogenic diabetes (MgD) conveys benefits for patients' care. Algorithms for selecting the patients to be genetically tested have been established in EuroCaucasians, but not in non-EuroCaucasian individuals. We assessed the diagnosis rate, the phenotype of MgD, and the relevance of selection criteria, according to ancestry in patients referred for a suspected MgD.

METHODS

Seven genes (GCK, HNF1A, HNF4A, HNF1B, ABCC8, KCNJ11, INS) were analyzed in 1975 adult probands (42% non-EuroCaucasians), selected on the absence of diabetes autoantibodies and ≥2 of the following criteria: age ≤40 years and body mass index <30 kg/m² at diagnosis, and a family history of diabetes in ≥2 generations.

RESULTS

Pathogenic/likely pathogenic variants were identified in 6.2% of non-EuroCaucasian and 23.6% of EuroCaucasian patients (OR 0.21, [0.16-0.29]). Diagnosis rate was low in all non-EuroCaucasian subgroups (4.1-11.8%). Common causes of MgD (GCK, HNF1A, HNF4A), but not rare causes, were less frequent in non-EuroCaucasians than in EuroCaucasians (4.1%, vs. 21.1%, OR 0.16 [0.11-0.23]). Using ethnicity-specific body mass index cutoffs increased the diagnosis rate in several non-EuroCaucasian subgroups.

CONCLUSION

The diagnosis rate of MgD is low in non-EuroCaucasian patients, but may be improved by tailoring selection criteria according to patients'ancestry.

Unusual severe radiation-induced toxicity in a patient with discoid lupus erythematosus: A case report and critical review of the literature

Data on the incidence and severity of radiation-induced toxicity in patients with systemic and/or cutaneous lupus erythematosus (SLE/CLE) are very limited. After reporting the case of a patient who experienced major toxicity and CLE flare in the irradiated area following breast irradiation, we conducted a comprehensive literature review of available data in this setting. The few retrospectives studies which have evaluated both the risk of toxicity in SLE/CLE patients and/or the potential induction or reactivation of SLE/CLE with radiotherapy have not shown differences between SLE/CLE patients and controls. Several other factors such as concurrent chemotherapy, a particular genetic background, or lupus treatments (essentially hydroxychloroquine) can explain severe radiation-induced toxicity. Therefore, patients with SLE/CLE should be irradiated like patients without SLE/CLE, with close monitoring during radiotherapy if other risk factors exist. Further studies examining a larger number of patients would probably allow a better understanding of the radiosensitivity of these patients.

Characterizing the Subcortical Structures in Youth with Congenital Heart Disease

BACKGROUND AND PURPOSE

Congenital heart disease is a leading cause of neurocognitive impairment. Many subcortical structures are known to play a crucial role in higher-order cognitive processing. However, comprehensive anatomic characterization of these structures is currently lacking in the congenital heart disease population. Therefore, this study aimed to compare the morphometry and volume of the globus pallidus, striatum, and thalamus between youth born with congenital heart disease and healthy peers.

MATERIALS AND METHODS

We recruited youth between 16 and 24 years of age born with congenital heart disease who underwent cardiopulmonary bypass surgery before 2 years of age (n = 48) and healthy controls of the same age (n = 48). All participants underwent a brain MR imaging to acquire high-resolution 3D T1-weighted images.

RESULTS

Smaller surface area and inward bilateral displacement across the lateral surfaces of the globus pallidus were concentrated anteriorly in the congenital heart disease group compared with controls (q < 0.15). On the lateral surfaces of bilateral thalami, we found regions of both larger and smaller surface areas, as well as inward and outward displacement in the congenital heart disease group compared with controls (q < 0.15). We did not find any morphometric differences between groups for the striatum. For the volumetric analyses, only the right globus pallidus showed a significant volume reduction (q < 0.05) in the congenital heart disease group compared with controls.

CONCLUSIONS

This study reports morphometric alterations in youth with congenital heart disease in the absence of volume reductions, suggesting that volume alone is not sufficient to detect and explain subtle neuroanatomic differences in this clinical population.

[Misdiagnosis of hidradenitis suppurativa continues to be a major issue. The R-ENS Verneuil study]

OBJECTIVE

To provide physicians with an understanding of the factors behind significant delays in the diagnosis of hidradenitis suppurativa (HS) in France.

PATIENTS AND METHODS

This prospective multicentre national study conducted from October 2015 to March 2016 included all patients consulting for HS. Patient data were collected by means of a standardized questionnaire. Univariate and multivariate analyses were conducted to collect factors associated with a significant time to diagnosis of at least 5.5years, defined as the period between the onset of initial clinical signs and the time of formal diagnosis.

RESULTS

The 16 participating centres enrolled 312 patients (62% women), of average age 35years. The average age at onset of HS was 22years. Before formal diagnosis by a dermatologist (64% of cases), 170 (54%), 114 (37%) and 45 (15%) patients had previously consulted at least 3, 5 and 10 general physicians, respectively. The average time between the initial clinical signs of HS, the first dermatology visit and the definitive diagnosis was 6.2 and 8.4 years, respectively. Active smoking (OR adjusted 1.85; P=0.027) and disease onset at a younger age (adjusted OR 0.92; P<0.001) were both associated with significant delays in diagnosis.

CONCLUSION

These results emphasized misdiagnosis among HS patients but did not evidence any association between either sociodemographic or economic characteristics and the existence of significant times to diagnosis.

Brain Temperature Is Increased During the First Days of Life in Asphyxiated Newborns: Developing Brain Injury Despite Hypothermia Treatment

BACKGROUND AND PURPOSE

Therapeutic hypothermia is the current treatment for neonates with hypoxic-ischemic encephalopathy. It is believed to work by decreasing the brain temperature and reducing the baseline metabolism and energy demand of the brain. This study aimed to noninvasively assess brain temperature during the first month of life in neonates with hypoxic-ischemic encephalopathy treated with hypothermia.

MATERIALS AND METHODS

Neonates with hypoxic-ischemic encephalopathy treated with hypothermia and healthy neonates were enrolled prospectively. MR imaging was used to identify the presence and extent of brain injury. MR imaging multivoxel spectroscopy was used to derive brain temperatures in the basal ganglia and white matter at different time points during the first month of life. Brain temperature measurements were compared between neonates with hypoxic-ischemic encephalopathy and healthy neonates.

RESULTS

Forty-three term neonates with hypoxic-ischemic encephalopathy treated with hypothermia had a total of 74 spectroscopy scans, and 3 healthy term neonates had a total of 9 spectroscopy scans during the first month of life. Brain temperatures were lower in neonates with hypoxic-ischemic encephalopathy during hypothermia, compared with the healthy neonates (respectively, on day 1 of life: basal ganglia, 38.81°C ± 2.08°C, and white matter, 39.11°C ± 1.99°C; and on days 2-3 of life: basal ganglia, 38.25°C ± 0.91°C, and white matter, 38.54°C ± 2.79°C). However, neonates with hypoxic-ischemic encephalopathy who developed brain injury had higher brain temperatures during hypothermia (respectively, on day 1 of life: basal ganglia, 35.55°C ± 1.31°C, and white matter, 37.35°C ± 2.55°C; and on days 2-3 of life: basal ganglia, 35.20°C ± 1.15°C, and white matter, 35.44°C ± 1.90°C) compared with neonates who did not develop brain injury (respectively, on day 1 of life: basal ganglia, 34.46°C ± 1.09°C, and white matter, 33.97°C ± 1.42°C; and on days 2-3 of life: basal ganglia, 33.90°C ± 1.34°C, and white matter, 33.07°C ± 1.71°C). Also, brain temperatures tended to remain slightly higher in the neonates who developed brain injury around day 10 of life and around 1 month of age.

CONCLUSIONS

Therapeutic hypothermia using current guidelines decreased the brain temperature of neonates with hypoxic-ischemic encephalopathy during the first days of life but did not prevent an early increase of brain temperature in neonates with hypoxic-ischemic encephalopathy who developed brain injury despite this treatment.

Injury to the Cerebellum in Term Asphyxiated Newborns Treated with Hypothermia

BACKGROUND AND PURPOSE

Until now, most studies of brain injury related to term neonatal encephalopathy have focused on the cerebrum and ignored the cerebellum. We sought to evaluate whether cerebellar injury occurs in term asphyxiated neonates.

MATERIALS AND METHODS

Asphyxiated neonates treated with hypothermia were enrolled prospectively. Severity of brain injury in the cerebrum was scored on each MR imaging obtained during the first month of life; cerebellar injury was recorded when mentioned in the imaging or autopsy report. In addition, for some of the neonates, the ADC and fractional anisotropy were measured in 4 regions of interest in the cerebellum.

RESULTS

One hundred seventy-two asphyxiated neonates met the criteria for hypothermia. Cerebellar injury was visible only on conventional imaging of 4% of the neonates for whom brain imaging was available, but it was reported in the autopsy report of 72% of the neonates who died. In addition, 41 of the asphyxiated neonates had a total of 84 ADC and fractional anisotropy maps. Neonates with brain injury described only in the cerebrum demonstrated ADC and fractional anisotropy changes similar to those of the neonates with brain injury in the cerebrum and cerebellum--increased ADC around day 10 of life and decreased fractional anisotropy on day 2-3 of life, around day 10 of life, and around 1 month of age.

CONCLUSIONS

The cerebellum may be injured in term neonates after birth asphyxia. These cerebellar injuries are only rarely visible on conventional imaging, but advanced neuroimaging techniques may help to identify them.

High-sensitivity C-reactive protein does not improve the differential diagnosis of HNF1A-MODY and familial young-onset type 2 diabetes: A grey zone analysis

AIM

Low plasma levels of high-sensitivity C-reactive protein (hs-CRP) have been suggested to differentiate hepatocyte nuclear factor 1 alpha-maturity-onset diabetes of the young (HNF1A-MODY) from type 2 diabetes (T2D). Yet, differential diagnosis of HNF1A-MODY and familial young-onset type 2 diabetes (F-YT2D) remains a difficult challenge. Thus, this study assessed the added value of hs-CRP to distinguish between the two conditions.

METHODS

This prospective multicentre study included 143 HNF1A-MODY patients, 310 patients with a clinical history suggestive of HNF1A-MODY, but not confirmed genetically (F-YT2D), and 215 patients with T2D. The ability of models, including clinical characteristics and hs-CRP to predict HNF1A-MODY was analyzed, using the area of the receiver operating characteristic (AUROC) curve, and a grey zone approach was used to evaluate these models in clinical practice.

RESULTS

Median hs-CRP values were lower in HNF1A-MODY (0.25mg/L) than in F-YT2D (1.14mg/L) and T2D (1.70mg/L) patients. Clinical parameters were sufficient to differentiate HNF1A-MODY from classical T2D (AUROC: 0.99). AUROC analyses to distinguish HNF1A-MODY from F-YT2D were 0.82 for clinical features and 0.87 after including hs-CRP. For the grey zone analysis, the lower boundary was set to miss<1.5% of true positives in non-tested subjects, while the upper boundary was set to perform 50% of genetic tests in individuals with no HNF1A mutation. On comparing HNF1A-MODY with F-YT2D, 65% of patients were classified in between these categories - in the zone of diagnostic uncertainty - even after adding hs-CRP to clinical parameters.

CONCLUSION

hs-CRP does not improve the differential diagnosis of HNF1A-MODY and F-YT2D.

Monoallelic ABCC8 mutations are a common cause of diazoxide-unresponsive diffuse form of congenital hyperinsulinism

ABCC8 encodes a subunit of the β-cell potassium channel (KATP ) whose loss of function is responsible for congenital hyperinsulinism (CHI). Patients with two recessive mutations of ABCC8 typically have severe diffuse forms of CHI unresponsive to diazoxide. Some dominant ABCC8 mutations are responsible for a subset of diffuse diazoxide-unresponsive forms of CHI. We report the analysis of 21 different ABCC8 mutations identified in 25 probands with diazoxide-unresponsive diffuse CHI and carrying a single mutation in ABCC8. Nine missense ABCC8 mutations were subjected to in vitro expression studies testing traffic efficiency and responses of mutant channels to activation by MgADP and diazoxide. Eight of the 9 missense mutations exhibited normal trafficking. Seven of the 8 mutants reaching the plasma membrane had dramatically reduced response to MgADP or to diazoxide (<10% of wild-type response). In our cohort, dominant KATP mutations account for 22% of the children with diffuse unresponsive-diazoxide CHI. Their clinical phenotype being indistinguishable from that of children with focal CHI and diffuse CHI forms due to two recessive KATP mutations, we show that functional testing is essential to make the most reliable diagnosis and offer appropriate genetic counseling.

Treatment-related morbidity in atypical teratoid/rhabdoid tumor: multifocal necrotizing leukoencephalopathy

BACKGROUND

Atypical teratoid/rhabdoid tumor (AT/RT) is an aggressive malignant brain tumor that, since it was first identified, has been treated with aggressive treatment regimens, e.g. high-dose chemotherapy with stem cell rescue and early radiotherapy. We reviewed our experience because of concerns with respect to treatment-related toxicity in our patients.

METHODS

Seven patients with a median age at presentation of 18 months were diagnosed with AT/RT between 1996 and 2006. Tumor location was supratentorial in 2 patients, in the posterior fossa in 4 and spinal in 1. Gross total resection was performed in 1 patient, subtotal resection in 5 and biopsy only in 1. Adjuvant treatment consisted of chemotherapy and radiotherapy in 5 patients.

RESULTS

Median progression-free survival was 4 months, and median overall survival was 7 months. Two children are alive at 44 and 102 months. Significant surgical and chemotherapy-related morbidity was seen. Biopsy-proven multifocal necrotizing leukoencephalopathy (MNL) was seen in one patient who is alive 44 months after diagnosis. Another patient who was thought to have recurrent tumor in the brainstem 9 months after diagnosis had imaging findings compatible with MNL.

CONCLUSION

Although improving results are reported for AT/RT using intensive treatment regimens, treatment-related morbidity is considerable in this young patient population.

Familial young-onset forms of diabetes related to HNF4A and rare HNF1A molecular aetiologies

OBJECTIVE

We have dissected the rare molecular anomalies that may affect hepatocyte nuclear factor-1a (HNF1A) and hepatocyte nuclear factor-4a (HNF4A) in patients with familial young-onset diabetes for whom HNF1A mutations have been excluded by sequence analysis.

METHODS

Eighty-four unrelatedHNF1A-negative patients with diabetes diagnosed before the age of 40 years, a family history of diabetes and the absence of features suggestive of Type 2 diabetes were included. We analysed by sequencing the HNF4A promoter and coding regions, the HNF1A promoter region and specific regions of HNF1A(B) and HNF1A(C) isoforms and searched for large deletions of HNF1A and HNF4A by multiplex ligation-dependent probe amplification (MLPA).

RESULTS

We identified five novel HNF4A mutations (5 ⁄ 84, 6%), including four missense and one in-frame deletion, and one mutation of the HNF1A promoter (1 ⁄ 84). Sequence analysis of isoform-specific coding regions of HNF1A did not reveal any mutation. We next identified two whole gene deletions of HNF1A and HNF4A, respectively (2 ⁄ 84, 2.4%).

CONCLUSIONS

Altogether, the search for rare molecular events in HNF1A and HNF4A led us to elucidate 8 ⁄ 84 (9.5%) of our HNF1A-negative cases.This study shows that genetic aetiologies remain to be elucidated in familial young-onset diabetes. It also highlights the difficulty of the differential diagnosis with Type 2 diabetes because of the wide clinical expression of monogenic young-onset diabetes and the absence of specific biomarkers.

ABCC8 and KCNJ11 molecular spectrum of 109 patients with diazoxide-unresponsive congenital hyperinsulinism

BACKGROUND

Congenital hyperinsulinism (CHI) is characterised by an over secretion of insulin by the pancreatic β-cells. This condition is mostly caused by mutations in ABCC8 or KCNJ11 genes encoding the SUR1 and KIR6.2 subunits of the ATP-sensitive potassium (K(ATP)) channel. CHI patients are classified according to their responsiveness to diazoxide and to their histopathological diagnosis (either focal, diffuse or atypical forms). Here, we raise the benefits/limits of the genetic diagnosis in the clinical management of CHI patients.

METHODS

ABCC8/KCNJ11 mutational spectrum was established in 109 diazoxide-unresponsive CHI patients for whom an appropriate clinical management is essential to prevent brain damage. Relationships between genotype and radiopathological diagnosis were analysed.

RESULTS

ABCC8 or KCNJ11 defects were found in 82% of the CHI cases. All patients with a focal form were associated with a single K(ATP) channel molecular event. In contrast, patients with diffuse forms were genetically more heterogeneous: 47% were associated with recessively inherited mutations, 34% carried a single heterozygous mutation and 19% had no mutation. There appeared to be a predominance of paternally inherited mutations in patients diagnosed with a diffuse form and carrying a sole K(ATP) channel mutation.

CONCLUSIONS

The identification of recessively inherited mutations related to severe and diffuse forms of CHI provides an informative genetic diagnosis and allows prenatal diagnosis. In contrast, in patients carrying a single K(ATP) channel mutation, genetic analysis should be confronted with the PET imaging to categorise patients as focal or diffuse forms in order to get the appropriate therapeutic management.

Familial cortical myoclonic tremor with epilepsy: the third locus (FCMTE3) maps to 5p

BACKGROUND

Familial cortical myoclonic tremor with epilepsy (FCMTE) is defined by autosomal dominant adult-onset cortical myoclonus (CM) and seizures in 40% of patients. Two loci, 8q23.3-q24.11 (FAME1/FCMTE1) and 2p11.1-q12.2 (FAME2/FCMTE2), were previously reported without an identified gene. Unlinked families argue for a third mutated gene.

METHODS

A genome-wide scan was performed in a large FCMTE family using Linkage-12 microarrays (Illumina). Refinement of the locus on 5p was performed by genotyping 13 polymorphic microsatellite markers in the 45 available family members.

RESULTS

This large French FCMTE family included 16 affected relatives. The first symptoms were CM in 5 patients (31.2%), seizures in 5 patients (31.2%), and both at the same time in 6 patients (37.5%). A total of 12.5% (2/16) had only CM without seizures. The genome-wide scan identified a single region on 5p15.31-p15, with a multipoint lod score of 3.66. Further genotyping of all family members confirmed that the region spans 9.31 Mb between D5S580 and D5S2096, 2-point lod scores reaching 6.3 at theta = 0 for D5S486. Sequencing of the SEMA5A and CTNND2 genes failed to detect mutations.

CONCLUSIONS

We report the clinical and genetic characteristics of a large familial cortical myoclonic tremor with epilepsy family. The third gene maps to 5p15.31-p15. Identification of the mutated gene is ongoing.

[Contribution of psychopathic traits to delinquent behaviors in a sample of high-school male students]

The aim of this study was to evaluate the contribution of psychopathic personality traits to delinquent behaviour after controlling for borderline personality traits, depressive symptomatology, dissociation and cannabis use in male adolescent delinquent behaviour.

METHOD

A sample of 155 young male participants (mean age=17+/-1.5) completed self-report questionnaires. Delinquent behaviour was assessed with the Antisocial behavior scales (ABS, Schawb-Stone et al., 1999) which include three subscales assessing behavior problems of different severity: conduct problems, assessing relatively mild behavior problems; less severe delinquency, assessing non-violent antisocial behavior; severe antisocial behavior, exploring relatively serious aggressive and antisocial behavior. The respondents were asked to report on a 5-point scale how many times (ranging from "0 times" to "5 or more times") they were involved in the described behaviors during the past year. In this study, only the two subscales assessing less severe delinquency and severe antisocial behavior were used. Personality psychopathic traits were assessed with the Youth psychopathic traits inventory (YPI; Andershed et al., 2002). It consists in three scales assessing interpersonal, affective (with callousness, which is considered as the core dimension of a psychopathy) and lifestyle traits of the psychopathic personality (alpha=0.90, alpha=0.81 and alpha=0.77, respectively). Other questionnaires assessed borderline personality traits (Borderline personality features scale for children), depression (Center for epidemiological studies-depression scale), dissociation (Adolescent dissociative experience scale) (alpha=0.83, 0.88 and 0.92 respectively) and cannabis use.

RESULTS

In the present study, the frequency of antisocial behaviour was important (55%): 7% of the adolescents had stolen a bike or a car at least once, 11% had committed a theft at least once, 36% had started a fight at least once, and 25% had threatened someone seriously or beaten up somebody at least once, 15% had had hurt someone badly in a physical fight so they had to be treated by a doctor or a nurse at least once, 21% had carried a blade, knife or gun at least once, 9% had been involved in a gang fight at least once, and 12% had carried a blade, knife or gun in school. A multiple regression analysis predicting antisocial behaviour in the total sample with the psychopathic and borderline traits, depressive and dissociative symptoms, alcohol and cannabis use, showed that delinquent behaviours were only predicted by alcohol and cannabis use and the psychopathic trait "callousness".

DISCUSSION

This study suggests the importance of callousness in explaining adolescent delinquent behaviour. Other psychopathological variables did not appear to influence delinquent behaviour in this sample.

Familial cortical myoclonic tremor with epilepsy (FCMTE): Clinical characteristics and exclusion of linkages to 8q and 2p in a large French family

INTRODUCTION

Familial cortical myoclonic tremor with epilepsy (FCMTE) is defined by an autosomal-dominant inheritance, adult onset of myoclonus of the extremities, infrequent epileptic seizures, a non-progressive course, polyspikes on electroencephalography (EEG), photosensitivity, giant somatosensory-evoked potentials (SEP), enhancement of C-reflex and a premyoclonus spike detected by jerk-locked EEG back-averaging. Two genes yet to be identified are mapped to 8q23.3-q24.1 and 2p11.1-q12.2.

METHODS

The present study involved five generations of a French family presenting with FCMTE, including 76 family members. Clinical analyses were performed in 39 living subjects and electrophysiological studies in five patients. Altogether, 27 relatives (21 living and six deceased) had the clinical characteristics of FCMTE, 17 of whom were analyzed. Linkage analyses were performed with microsatellites encompassing the two known loci (8q 23.3-q24.1 and 2p11.1-q12.2).

RESULTS

Mean age at onset in the 17 living patients was 28.8 years (range 24-41). All had myoclonus/cortical tremor, and 11/17 had generalized tonic-clonic seizures. Other clinical symptoms were photosensitivity (16 cases), partial seizures (five cases), sensitivity to starvation/exercise (six cases) and vibration (four cases), ophthalmic migraine (six cases) and gait disorders (10 cases). Electrophysiological studies confirmed the FCMTE diagnosis in the five studied patients. Of the remaining relatives, 14 were considered healthy (asymptomatic subjects aged more than 40years) and eight were of unknown status (asymptomatic aged lesser than 40years). The pattern of inheritance was consistent with autosomal-dominant inheritance, although the two loci responsible for FCMTE were excluded.

CONCLUSION

This large family highlights some unusual clinical characteristics and suggests the presence of a third gene. Genetic research is ongoing to identify the mutated gene.

Spectrum of SCN1A gene mutations associated with Dravet syndrome: analysis of 333 patients

INTRODUCTION

Mutations in the voltage-gated sodium channel SCN1A gene are the main genetic cause of Dravet syndrome (previously called severe myoclonic epilepsy of infancy or SMEI).

OBJECTIVE

To characterise in more detail the mutation spectrum associated with Dravet syndrome.

METHODS

A large series of 333 patients was screened using both direct sequencing and multiplex ligation-dependent probe amplification (MLPA). Non-coding regions of the gene that are usually not investigated were also screened.

RESULTS

SCN1A point mutations were identified in 228 patients, 161 of which had not been previously reported. Missense mutations, either (1) altering a highly conserved amino acid of the protein, (2) transforming this conserved residue into a chemically dissimilar amino acid and/or (3) belonging to ion-transport sequences, were the most common mutation type. MLPA analysis of the 105 patients without point mutation detected a heterozygous microrearrangement of SCN1A in 14 additional patients; 8 were private, partial deletions and six corresponded to whole gene deletions, 0.15-2.9 Mb in size, deleting nearby genes. Finally, mutations in exon 5N and in untranslated regions of the SCN1A gene that were conserved during evolution were excluded in the remaining negative patients.

CONCLUSION

These findings widely expand the SCN1A mutation spectrum identified and highlight the importance of screening the coding regions with both direct sequencing and a quantitative method. This mutation spectrum, including whole gene deletions, argues in favour of haploinsufficiency as the main mechanism responsible for Dravet syndrome.

Does the Pattern of Repeated Sprint Ability Differ between Sickle Cell Trait Carriers and Healthy Subjects?

Sickle cell trait (SCT) is a genetic abnormality affecting the synthesis of normal haemoglobin [Hb] and is the heterozygous form of sickle cell anaemia. The aim of the present study was to compare the ability to repeat maximal cycling sprints (RSA; repeated sprint ability) between SCT carriers (SCT group, n = 7) and a control group with normal haemoglobin [Hb] (n = 7). The two groups performed a 10-s maximal cycling sprint in order to determine the peak power output (P(peak10)). They then performed an RSA test that consisted of five 6-s maximal cycling sprints interspersed with 24 s of passive recovery. For each sprint, the peak power output (P(peak6)) and the work over the 6-s (W6) were calculated. The sum of each W6 developed during the test was considered to be the total work (W(tot)). The decrements over the repeated sprints for P(peak6) (P(6dec)) and W6 (W(6dec)) were also determined. We found no difference in P(peak10), W(tot) and W(6dec) between the two groups. However, the drop in P(peak6) and W6 during the RSA test appeared earlier in the SCT group and the decrease in P(peak6) over the RSA test was greater in the SCT group than in the control group (p < 0.05). In conclusion, we found that: 1) maximal anaerobic performance determined during a single sprint was not altered by SCT, but 2) repeated sprint ability was different in SCT carriers compared with sportsmen with normal Hb.

Coarctation of the aorta: pre and postoperative evaluation with MRI and MR angiography; correlation with echocardiography and surgery

AIMS

To compare MRI and MRA with Doppler-echocardiography (DE) in native and postoperative aortic coarctation, define the best MR protocol for its evaluation, compare MR with surgical findings in native coarctation.

MATERIALS AND METHODS

136 MR studies were performed in 121 patients divided in two groups: Group I, 55 preoperative; group II, 81 postoperative. In group I, all had DE and surgery was performed in 35 cases. In group II, DE was available for comparison in 71 cases. MR study comprised: spin-echo, cine, velocity-encoded cine (VEC) sequences and 3D contrast-enhanced MRA.

RESULTS

In group I, diagnosis of coarctation was made by DE in 33 cases and suspicion of coarctation and/or aortic arch hypoplasia in 18 cases. Aortic arch was not well demonstrated in 3 cases and DE missed one case. There was a close correlation between VEC MRI and Doppler gradient estimates across the coarctation, between MRI aortic arch diameters and surgery but a poor correlation in isthmic measurements. In group II, DE detected a normal isthmic region in 31 out of 35 cases. Postoperative anomalies (recoarctation, aortic arch hypoplasia, kinking, pseudoaneurysm) were not demonstrated with DE in 50% of cases.

CONCLUSIONS

MRI is superior to DE for pre and post-treatment evaluation of aortic coarctation. An optimal MR protocol is proposed. Internal measurement of the narrowing does not correspond to the external aspect of the surgical narrowing.

Cerebral venous sinus thrombosis in children: risk factors, presentation, diagnosis and outcome

Neuroimaging and management advances require review of indications for excluding cerebral venous sinus (sinovenous) thrombosis (CSVT) in children. Our goals were to examine (i) clinical presentations of CSVT, (ii) prothrombotic risk factors and other predisposing events, (iii) clinical and radiological features of brain lesions in CSVT compared with arterial stroke, and (iv) predictors of outcome. We studied 42 children with CSVT from five European paediatric neurology stroke registries. Patients aged from 3 weeks to 13 (median 5.75) years (27 boys; 64%) presented with lethargy, anorexia, headache, vomiting, seizures, focal signs or coma and with CSVT on neuroimaging. Seventeen had prior chronic conditions; of the 25 previously well patients, 23 had recent infections, eight became dehydrated and six had both. Two children had a history compatible with prior CSVT. Anaemia and/or microcytosis (21 probable iron deficiency, five haemolytic, including two with sickle cell disease and one with beta-thalassaemia) was as common (62%) as prothrombotic disorder (13/21 screened). High factor VIII and homozygosity for the thermolabile methylene tetrahydrofolate reductase polymorphism were the commonest prothrombotic disorders. The superficial venous system was involved in 32 patients, the deep in six, and both in four. Data on the 13 children with bland infarction and the 12 with haemorrhage in the context of CSVT were compared with those from 88 children with ischaemic (AIS) and 24 with haemorrhagic (AHS) arterial stroke. In multiple logistic regression, iron deficiency, parietal infarction and lack of caudate involvement independently predicted CSVT rather than arterial disease. Five patients died, three acutely, one after recurrence and one after 6 months being quadriparetic and blind. Follow-up ranged from 0.5 to 10 (median 1) years. Twenty-six patients (62%) had sequelae: pseudotumour cerebri in 12 and cognitive and/or behavioural disabilities in 14, associated with epilepsy in three, hemiparesis in two and visual problems in two. Eighteen patients, including six with haemorrhage, were anticoagulated. Older age [odds ratio (OR) 1.54, 95% confidence limits (CI) 1.12, 2.13, P = 0.008], lack of parenchymal abnormality (OR 0.17, 95% CI 0.02, 1.56, P = 0.1), anticoagulation (OR 24.2, 95% CI 1.96, 299) and lateral and/or sigmoid sinus involvement (OR 16.2, 95% CI 1.62, 161, P = 0.02) were independent predictors of good cognitive outcome, although the last predicted pseudotumour cerebri. Death was associated with coma at presentation. Of 19 patients with follow-up magnetic resonance (MR) venography, three had persistent occlusion, associated with anaemia and longer prodrome. A low threshold for CT or MR venography in children with acute neurological symptoms is essential. Nutritional deficiencies may be modifiable risk factors. A paediatric anticoagulation trial may be required, after the natural history has been further established from registries of cases with and without treatment.

The paediatric liver transplantation program at the Université catholique de Louvain

The Paediatric Liver Transplant Program at Saint-Luc University Clinics constitutes a substantial single centre experience, including 667 transplantations performed between March 1984 and April 2003, and the history of this program reflects the tremendous progress in this field since twenty years. Liver transplantation in children constitutes a considerable undertaking and its results depend on multiple, intermingled risk factors. An analysis of the respective impact of several surgical and immunological parameters on patient/graft outcome and allograft rejection after paediatric liver transplantation showed a significant learning curve effect as well as the respective impact of pre-transplant diagnosis on survival and of primary immunosuppression on the rejection incidence. The introduction of living related liver transplantation in 1993 not only permitted to provide access to liver replacement in as many as 74% more candidate recipients, but also resulted in better graft survival and reduced retransplantation rate. The results of a recent pilot study suggest that steroid avoidance is not harmful, and could even be beneficial for paediatric liver recipients, particularly regarding growth, and that combining tacrolimus with basiliximab (anti-CD25 chimeric monoclonal antibody) for steroid substitution appears to constitute a safe alternative in this context. The long-term issues represent the main future challenges in the field, including the possibility of a full rehabilitation through immunosuppression withdrawal and tolerance induction, the development of adolescence transplant medicine, and the risk of early atherogenesis in the adulthood.

Unusual upper cervical fracture in a 1-year-old girl

Injuries to the child's cervical spine are rare and, unlike adults, most common from the occiput to C3. Most odontoid fractures in children occur through the basilar synchondrosis and only the dens is displaced anteriorly. The authors report the clinical and radiologic evaluation of a child who sustained an unusual cervical injury during a motor vehicle accident. The lesion consisted of an epiphyseal fracture-separation between the body and the neural arches of C2. There was also an associated spinal cord lesion.

Living-related liver transplantation in children at Saint-Luc University Clinics: a seven year experience in 77 recipients

The Brussels series of living related liver transplantation (LRLT) in 77 children (< 15 years) is reviewed. Median (range) recipient age at liver transplantation was 1.1 year (0.4-13.1). The main indication for LT was biliary atresia in 55/77 cases (71%). The living-related donor was one of the parents in 74 instances. Hepatic segments 2-3 (n = 67) or 2-3-4 (n = 10) were implanted orthotopically, with a median (range) graft weight to recipient body weight ratio of 3.17% (0.91-8.08). No severe complications or significant long-term sequelae were encountered in the living donors. One and five year survival rates were 92% and 89% for the patients, and 90% and 86% for the grafts, respectively. The retransplantation rate was 2/77 (2.6%), the indication being chronic rejection in both instances. In conclusion, LRLT is now a validated procedure in the living donors as well as in pediatric recipients with chronic or acute liver diseases. In the current context of organ shortage, it provides a valuable alternative to cadaveric LT.

Adenylosuccinase deficiency: an unusual cause of early-onset epilepsy associated with acquired microcephaly

Adenylosuccinase deficiency, an autosomal recessive inborn error of purine synthesis, was first described in 1984 by Jaeken and Van den Berghe (reviewed in J Inher Metab Dis 20;1997:193). The cardinal features are variable psychomotor delay often accompanied by epilepsy and autistic features. Diagnosis is made by detection of abnormal purine metabolites in body fluids. We report a girl who presented with early onset epilepsy, associated with acquired microcephaly and severe psychomotor retardation, as the most prominent symptoms.

Polymicrogyria and motor neuropathy in Micro syndrome

Micro syndrome is a rare condition in which congenital cataracts, microphthalmia, and facial dysmorphism are associated with severe neurological disorders, namely: microcephaly and psychomotor retardation. We report on polymicrogyria and motor neuropathy in a patient with Micro syndrome. These findings provide new insights into developmental defects underlying motor and mental disabilities.

Diverse genetic mechanisms operate to generate atypical betaS haplotypes in the population of Guadeloupe

In a survey of the chromosomal background associated with the sickle cell gene in Guadeloupe, a French Caribbean island, we identified 37 unrelated patients with sickle cell disease (27 SS, nine SC, and one S-beta-thalassemia) of 477 unrelated sickle cell patients where the beta3 gene was linked to 20 different atypical haplotypes. These atypical chromosomes account for about 5% of the overall betaS chromosomes in this population. To investigate the origin of these atypical betaS haplotypes, we performed extensive typing of betaS and betaA chromosomes. Twenty-two different 5' subhaplotypes were identified among the betaS chromosomes. Fifteen of 20 different atypical haplotypes are likely to be the product of recombination by a single crossover around the <<hot-spot>> 5' to the beta-globin gene, or between a major betaS haplotype and one of the betaS haplotypes present in the population. The remaining cases require genetic mechanisms (gene conversions, additional substitutions in a given haplotype) other than crossovers to generate these atypical haplotypes.

Urachal neuroblastoma: first case report

Tumours of the urachus are exceptional in children. They represent 0.01% of all tumours and consist of mucosecretory adenocarcinoma and, more rarely, transitional cell carcinoma. We report a 6-month-old child with a urachal mass which, following biopsy, was shown to be a neuroblastoma.

Madelung deformity as a feature of the Leri-Layani-Weill syndrome or dyschondrosteosis

We report and discuss a case of a Madelung's deformity seen on a wrist roentgenogram of a young girl who is referred for short stature evaluation, which led to the diagnosis of Léri-Weill syndrome or dyschondrosteosis. The authors stress that it is possible to make an accurate diagnosis on a single standard roentgenogram, at low cost, if the different diagnostic criteria are known.

Sickle cell disorder, beta-globin gene cluster haplotypes and alpha-thalassemia in neonates and adults from Guadeloupe

We have studied haplotype of beta(S) chromosome and alpha-globin gene status in 534 patients (255 adults and 279 children of whom 159 neonates) from Guadeloupe with various sickle cell-related conditions, namely SS (n = 298), SC (n = 170), S-beta-thal (n = 56), and other rare forms (n = 10). Haplotype data on beta(S) chromosomes confirm our previous observation that Benin type is the most prevalent (75%) beta(S) chromosome in Guadeloupe, in disagreement with the historical records. Comparison of the frequency of distribution of various beta(S) haplotypes between neonates and adults on the one hand and between SS and SC cases on the other shows that the current beta(S) haplotype distribution in this island is not distorted by haplotype-related differential survival. We also show that the frequency of alpha-thalassemia (-3.7 kb) in Guadeloupe is one of the highest recorded in this region involved in Atlantic slave trade and also failed to reveal any age-dependent increase in frequency. We conclude that the African component of Guadeloupe is distinct from that of Brazil and Cuba but is close to that of Jamaica.

[Chronic recurrent multifocal osteomyelitis. A diagnosis to be called to mind]

Chronic recurrent multifocal osteomyelitis is a rare disorder that affects children and teenagers. Clinically, it is characterized by insidious onset of local swelling and pain in several metaphyses. A symmetric, recurrent and multifocal pattern is usual. Spinal involvement is possible. Inconstant association with a cutaneous affection (palmoplantar pustulosis, acne fulminans, psoriasis), or less frequently with an inflammatory chronic gut disorder is described. Pathogenesis usually recognized is an enthesopathy. Enthesitis may progress to the osseous part of the enthese and produce an aseptic chronic osteomyelitis. Biopsy specimen with culture is certainly necessary to rule out bacterial osteomyelitis and bone tumor. It is particularly true when the bone lesion is isolated. Disease course is benign and self-limited. The clinical course is characterized by recurrences and remission occurring for 6 to 10 years. Treatment based on non steroid antiinflammatory drugs is usually effective.

Efficiency of prenatal counselling for sickle cell disease in Guadeloupe

As in most caribbean countries, Sickle Cell Disease (SCD) is a major public health problem in Guadeloupe. A prenatal counselling program was developed, at an early stage of pregnancy, for at-risk couples. Over a 6 year period, 144 couples at-risk of having a child with homozygous sickle cell (SS: n = 103) or sickle cell C disease (SC: n = 41) were seen for prenatal counselling. Among those belonging to the SS risk group, 64 (62%) underwent prenatal diagnosis (PND), which allowed identification of 27 SS fetuses, with an induced abortion rate of 70%. Among those of the SC risk group, 14 (34%) accepted PND and the diagnosis of SC was made in 5 cases with an induced abortion rate of 60%. Factors, appeared to play a role in seeking PND and induced abortion, were the type of risk (SS or SC), multiparity, existence of affected child in the family and gestational age at the time of counselling. Our experience reveals that, an early prospective identification of at-risk couples combined with education to increase the awareness of the problem at the individual and population level need to be achieved to further improve the efficiency of our prevention program.

Molecular characterization of beta-thalassemia mutations in Guadeloupe

In order to perform genetic counselling and prenatal diagnosis of Hb-S-beta-thalassemia disease and beta-thalassemia, we have delineated the spectrum of beta-thalassemia alleles in the Guadeloupean population. A sample of 63 unrelated families was analyzed including 70 beta-thalassemia carriers, 52 Hb-S-beta-thalassemia, and 8 patients with different beta-thalassemic hemoglobinopathies. Among the eleven mutations identified, four of them [-29 (A --> G), IVS-I-5 (G --> A), IVS-II-1 (G --> A), and IVS-I-5 (G --> C)] account for 77.6% of the beta-thalassemia chromosomes present in the studied families. The seven other variants, CD 24 (T --> A), IVS-I-2 (T --> C), Poly A (T --> C), -88 (C --> T), IVS- 11-849 (A --> G), Hb E, and Hb Lepore are less frequent. As a result, Hb S-beta+-thalassemia type 1 (low Hb A values: 5-15%) together with Hb S-beta(omicron)-thalassemia phenotypes are as frequent as Hb S-beta+-thalassemia type 2 (high Hb A values: 20-30%) in the Guadeloupean population. Patients with Hb S-beta+-thalassemia type 2 have milder hematological manifestations of the disease compared to patients with Hb S-beta(omicron)-thalassemia and Hb S-beta+-thalassemia type 1. This first report on the type and nature of beta-thalassemia mutations in Guadeloupe shows that prenatal diagnosis of Hb S-beta-thalassemia and beta-thalassemia should be feasible by direct detection of point mutation in most cases.

Prospective sandwich enzyme-linked immunosorbent assay for serum galactomannan: early predictive value and clinical use in invasive aspergillosis

BACKGROUND

The delay between the onset of invasive aspergillosis and the start of antifungal therapy is crucial for the patient's recovery. Early diagnosis is difficult in cancer patients through lack of precocious specific signs. We have investigated the clinical usefulness of circulating Aspergillus antigen monitoring in pediatric hematology patients with a new sensitive sandwich enzyme-linked immunosorbent assay.

METHODS

A prospective study was conducted by assessing circulating galactomannan levels in high risk patients. Thirty-seven patients studied during an 18-month period were evaluated twice weekly during neutropenic phases with the sandwich enzyme-linked immunosorbent assay for serum Aspergillus galactomannan.

RESULTS

Twelve patients had one or more episodes of positive circulating galactomannan detection, 10 of whom developed presumptive invasive aspergillosis. The clinical and radiologic signs occurred at a mean of 13.4 days (range, 0 to 48) after circulating galactomannan detection and reversed in 6 patients treated with amphotericin B at the same time circulating galactomannan detection became negative. Reappearance of circulating galactomannan was observed during subsequent neutropenic periods in 3 patients.

CONCLUSIONS

The detection of galactomannan at concentrations as low as 1 ng/ml can be useful for the early initiation of antifungal therapy and monitoring treatment in clinically documented lung aspergillosis. This technique coupled with chest computed tomography could help to restrict the need of invasive diagnostic procedures in fragile patients.

Sonographic diagnosis and follow-up of diffuse neutropenic colitis: case report of a child treated for osteogenic sarcoma

The sonographic features of total neutropenic colitis in a 14-year-old girl with osteogenic sarcoma are presented. Sonography disclosed characteristic diffuse thickening of the colonic wall with hyperechoic bowel mucosa. Serial sonograms were performed to monitor the progress of the disease.

[Oropharyngeal flora. Epidemiologic survey of prevalence]

OBJECTIVES

Epidemiological surveys which are not frequently carried out in medical practice should provide useful information for the choice of antibiotics to be prescribed in community-acquired infections particularly with the recent development of therapeutic difficulties due to resistant strains. We therefore analyzed the prevalent pharyngeal flora in a general patient population.

METHODS

The study was conducted during a single 24-hour period in 1991 by 43 general practitioners and included 645 subjects consulting for benign affections. No patient selection was made. Two pharyngeal swabs were obtained from each subject and cultured in aerobic and anaerobic conditions. Internationally accepted methods for identifying bacteria in pharyngeal samples all performed by one well-equipped laboratory. Beta-lactamase activity was determined with the nitrocephine technique, both directly and after culture.

RESULTS

Patient age varied from 16 to 45 years; most (68.5%) consulted for reasons other than ear-nose-throat affections. Only 41 patients (4.3%) consulted for sore throat and 65.4% had not received antibiotics for at least 6 months. Haemophilus influenzae was found in 59.6% of the patients, 20% of the strains were beta-lactamase producers as were 83.7% of the Moraxella catarrhalis strains identified.

CONCLUSION

These factors are indicators of potential risk of therapeutic failure when using beta-lactams unstable to beta-lactamases for the treatment of pharyngeal infections.

Hemoglobin Roseau-Pointe a Pitre alpha 2 beta 2(90) (F6) Glu----Gly: a new hemoglobin variant with slight instability and low oxygen affinity

A Dominican neonate carrying a new abnormal hemoglobin, hemoglobin Roseau Pointe-à-Pitre alpha 2 beta 2(90)(F6) Glu----Gly, was detected in Guadeloupe during application of a cord blood screening program. This variant behaved in isoelectrofocusing as an Hb D, and displayed instability and low whole blood oxygen affinity. In the affected family it was present, either isolated, or in association with a beta+ thalassemia trait.