[Conradi-Hünermann-Happle syndrome]

BACKGROUND

Conradi-Hünermann-Happle syndrome is caused by a mutation in the emopanil binding protein-gene (EBP), which encodes the enzyme 3β-hydroxysteroid-dehydrogenase-δ8,7 isomerase. This gene is involved in cholesterol metabolism.

CASE DESCRIPTION

In this case report we describe a girl aged 19 months with Conradi-Hünermann-Happle syndrome. This syndrome was characterized in this patient by a complete erythrodermia directly after birth, followed by linear ichthyosis, shortened upper arms and thighs, vertebral anomalies resulting in progressive scoliosis and cataract. The patient's mother was found also to suffer from the Conradi-Hünermann-Happle syndrome. As a child she had linear ichthyosis, difference in leg length and congenital alopecia in a linear pattern.

CONCLUSION

For diagnosis and treatment of children with such a rare syndrome a multidisciplinary approach is essential. Multidisciplinary collaboration guarantees an appropriate follow-up for the patient and the family.

Ehlers-Danlos arthrochalasia type (VIIA-B)--expanding the phenotype: from prenatal life through adulthood

The Ehlers-Danlos syndromes (EDS) form a clinically and genetically heterogeneous group of inherited connective-tissue disorders characterized by joint hypermobility, tissue fragility and skin abnormalities. Six subtypes have been well characterized based on clinical features and molecular genetic abnormalities. The arthrochalasia type EDS (formerly types VIIA and B) is characterized by severe generalized joint hypermobility with multiple dislocations including congenital bilateral dislocation of the hips, muscular hypotonia and distinct dysmorphic features. The diagnosis of the arthrochalasia type EDS is of importance in the neonatal period because of consequences of physical disability in later life. However, the differential diagnosis may be difficult because of overlap with other hypermobility syndromes. In addition, the significant hypotonia may direct the physician toward various neuromuscular diagnoses. As patients become older, the hypotonia decreases and facial features become less distinct. In this report, we describe seven patients at different ages. Timing of diagnosis varied from prenatal life to adult age. The diagnosis of EDS type VII was confirmed by biochemical studies or mutation analysis showing characteristic mutations in COL1A1 and COL1A2. These mutations result in skipping of exon 6, which leads to defective collagen synthesis. For physicians treating patients with EDS type VII, achieving mobility for the patient is the greatest challenge and it may be impossible because of recurrent dislocations of nearly all joints in severe cases.

MLL2 mutation spectrum in 45 patients with Kabuki syndrome

Kabuki Syndrome (KS) is a rare syndrome characterized by intellectual disability and multiple congenital abnormalities, in particular a distinct dysmorphic facial appearance. KS is caused by mutations in the MLL2 gene, encoding an H3K4 histone methyl transferase which acts as an epigenetic transcriptional activator during growth and development. Direct sequencing of all 54 exons of the MLL2 gene in 45 clinically well-defined KS patients identified 34 (75.6%) different mutations. One mutation has been described previously, all others are novel. Clinically, all KS patients were sporadic, and mutations were de novo for all 27 families for which both parents were available. We detected nonsense (n=11), frameshift (n=17), splice site (n=4) and missense (n=2) mutations, predicting a high frequency of absent or non-functional MLL2 protein. Interestingly, both missense mutations located in the C-terminal conserved functional domains of the protein. Phenotypically our study indicated a statistically significant difference in the presence of a distinct facial appearance (p=0.0143) and growth retardation (p=0.0040) when comparing KS patients with an MLL2 mutation compared to patients without a mutation. Our data double the number of MLL2 mutations in KS reported so far and widen the spectrum of MLL2 mutations and disease mechanisms in KS.

Healthcare transition in persons with intellectual disabilities: general issues, the Maastricht model, and Prader-Willi syndrome

In current healthcare, transitional healthcare is a very important and timely issue. Thanks to the major advances made in medical care and technology, many children with childhood onset diseases and/or genetic syndromes survive to adulthood. These children are at risk of not being provided with adequate healthcare as they reach adulthood. Healthcare transition is an essential part of healthcare provision, referred to as the shift from one type of healthcare to another. In Maastricht, we developed a transition/out clinic led by a medical doctor specialized in persons with intellectual disability (ID), together with a clinical geneticist. We aim to coordinate healthcare issues based on guidelines if available. Also questions concerning living, daily activities, relations, sexuality, and sterilization can be discussed. The aging process of persons with ID has been a topic of interest in recent years. Little is known about the aging process of people with specific syndromes, except for persons with Down syndrome. We present some data of a recent questionnaire study in persons with Prader-Willi syndrome. In only 50% in persons with a clinical diagnosis genetic test results could be reported. The majority of persons were obese. Diabetes mellitus, hypertension, skin problems, sleep apnea, and hormonal problems like osteoporosis and hypothyroidism were common. Psychiatric problems were frequent, especially in the persons with uniparental disomy. Osteoporosis and sleep apnoea seem to be underestimated. Further longitudinal research is necessary for a better understanding of the aging process in PWS.

Multifocal osteomyelitis in a child: a rare manifestation of cat scratch disease: a case report and systematic review of the literature

We present a case of a 9-year-old immunocompetent girl who presented with pain in her left elbow and a painful swelling at her left clavicle. She had no lymphadenopathy or fever. Four hot spots were seen at her left clavicle, proximal and distal left humerus and lumbo-sacral spine on a bone scan. A magnetic resonance imaging showed an inflammatory process with bone destruction at her clavicle. Serological testing and polymerase chain reaction performed on a bone biopsy identified a Bartonella henselae infection. She was treated with rifampin and trimethoprim-sulphamethoxazole. After a relapse half a year later, the patient recovered fully. Multifocal osteomyelitis is a rare manifestation of cat scratch disease in children.

Kabuki syndrome: Clinical data in 20 patients, literature review, and further guidelines for preventive management

The Kabuki syndrome, or Niikawa-Kuroki syndrome, is a clinically recognizable syndrome of unknown etiology. Clinical findings include early hypotonia, joint laxity, developmental delay, facial dysmorphism, persistent fetal fingertip pads, cleft palate, hypodontia, lip nodules, heart defects, and a variety of other structural defects. Behavior in general is social and pleasant. In collaboration with the Dutch Kabuki Network, we evaluated the medical data of 20 individuals diagnosed with the syndrome and compared them with data from the literature. In our literature review we used convincing cases only. Frequent findings in the oral region are under-reported in the literature: apart from the cleft palate (in about 50%), hypodontia with predominantly absence of the upper lateral incisors, and a full lower lip with symmetrical nodules, or (in a minority) lip-pits are frequent findings. Also under-reported is the presence of a thickened nuchal fold during pregnancy and hydrops in the neonatal period. Clinical recognition in the neonate is difficult. Towards early puberty acute and serious weight excess has been experienced. We suggest that a cytogenetic abnormality should be ruled out in all cases. We provide further guidelines for preventive management.

Prader-Willi syndrome: causes of death in an international series of 27 cases

Prader-Willi syndrome (PWS) is a complex condition with many medical and psychological features. In individuals with this syndrome, causes of death were studied. Data of 27 case reports were collected. Ages at death ranged from neonatal to 68 years. None of the individuals were treated with growth hormone (GH). Most cases were not completely documented and autopsy was performed in a minority of cases only. In five cases, death was considered not to be causally related to PWS. Hypotonia with hypoventilation was noted in the babies, and acute respiratory illness with unexpected sudden death was experienced in young children with PWS. Two young children died after a short period of fever and gastroenteritis. Obesity and its complications leading to death were pronounced in the adult group. One (possibly two) adult(s) died from gastric dilatation and shock. Based on these data, some cautious conclusions can be drawn. In babies with PWS hypoventilation is a risk factor; upper airway infection may be more serious than anticipated and any other clinical features pointing to an infection should be taken very seriously. Therefore, young infants with PWS hospitalized with an upper airway infection and/or hypoventilation or gastroenteritis symptoms, should be closely monitored. Early diagnosis and prevention of overweight is a major factor in preventing early causes of death in individuals with PWS. In the adult group, weight reduction is important but difficult to manage. Sleep apnea should be recognized and treated. Pain in the upper stomach and/or vomiting should be taken as a possible sign of acute intestinal dilatation; intravenous support may be life saving.

Auditory canal atresia, humeroscapular synostosis, and other skeletal abnormalities: confirmation of the autosomal recessive "SAMS" syndrome

A second girl with the unique combination of auditory canal atresia and scapulohumeral synostosis is reported. This patient also had bilateral clubfeet and genital abnormalities. The other patient reported with this syndrome and the presently reported child both had consanguineous parents. Mental development was normal in both children. The acronym SAMS (Short stature, Auditory canal atresia, Mandibular hypoplasia, and Skeletal abnormalities) was suggested to describe the main manifestations in this syndrome.