Why study inner ear hair cell mitochondria?

In several systems of the body (muscle, liver, nerves), new studies have examined the internal structure of mitochondria and brought to light striking new findings about how mitochondria are constructed and how their structure affects cell function. In the inner ear field, however, we have little structural knowledge about hair cell and supporting cell mitochondria, and virtually none about mitochondrial subtypes or how they function in health and disease. The need for such knowledge is discussed in this short review.

Severe digital malformations in a rare variant of fibrodysplasia ossificans progressiva

A 16-year-old girl with a history of nontraumatic swelling of both forearms, osteochondromas of the knees, heterotopic ossification of the neck and back, severe malformations of all digits with hypoplastic or absent nails, alopecia partialis of the scalp, and moderate cognitive impairment was seen for diagnostic evaluation. Whole exome sequencing identified an activating mutation of ACVR1 (c.983G > A; p.Gly328Glu) which confirmed a suspected FOP variant. The delayed diagnosis of an FOP variant in this patient could have been avoided if the significance of severe digital malformations had been recognized, especially in the setting of progressive heterotopic ossification.

Heterotopic ossifications and Charcot joints: Congenital insensitivity to pain with anhidrosis (CIPA) and a novel NTRK1 gene mutation

Congenital insensitivity to pain with anhidrosis (CIPA), also known as hereditary sensory and autonomic neuropathy type IV (HSAN-IV), is a rare and severe autosomal recessive disorder. We report on an adult female patient whose clinical findings during childhood were not recognized as CIPA. There was neither complete anhidrosis nor a recognizable sensitivity to heat. Tumorlike swellings of many joints and skeletal signs of Charcot neuropathy developed in adolescence which, together with a history of self-mutilation, led to a clinical suspicion of CIPA confirmed by identification of a novel homozygous variant c.1795G > T in the NTRK1 gene in blood lymphocytes. Both parents were heterozygous for the mutation. The variant predicts a premature stop codon (p.Gly599Ter) and thus represents a pathogenic variant; the first reported in the Southeastern European population.

IGF1R Gene Alterations in Children Born Small for Gestitional Age (SGA)

BACKGROUND:

Small for gestational age (SGA)-born children are a heterogeneous group with few genetic causes reported. Genetic alterations in the IGF1 receptor (IGF1R) are found in some SGA children.

AIM:

To investigate whether alterations in IGF1R gene are present in SGA born children.

PATIENTS AND METHODS:

We analysed 64 children born SGA who stayed short (mean -3.25 ± 0.9 SDS) within the first 4 years of age, and 36 SGA children who caught up growth (0.20 ± 1.1 SDS). PCR products of all coding IGF1R exons were screened by dHPLC followed by direct sequencing of conspicuous fragments to identify small nucleotide variants. The presence of IGF1R gene copy number alterations was determined by Multiplex Ligation-dependent Probe Amplification (MLPA).

RESULTS:

The cohort of short SGA born children revealed a heterozygous, synonymous variant c.3453C > T in one patient and a novel heterozygous 3 bp in-frame deletion (c.3234_3236delCAT) resulting in one amino acid deletion (p.Ile1078del) in another patient. The first patient had normal serum levels of IGF1. The second patient had unusually low IGF1 serum concentrations (-1.57 SD), which contrasts previously published data where IGF1 levels rarely are found below the age-adjusted mean.

CONCLUSIONS:

IGF1R gene alterations were present in 2 of 64 short SGA children. The patients did not have any dysmorphic features or developmental delay. It is remarkable that one of them had significantly decreased serum concentrations of IGF1. Growth response to GH treatment in one of the patients was favourable, while the second one discontinued the treatment, but with catch-up growth.

LHX4 Gene Alterations: Patient Report and Review of the Literature

LHX4 mutations are rare in combined pituitary hormone deficiency, and even rarer in isolated GHD. We describe a 14 years old boy who was referred for investigation of short stature. Convergent strabismus, nystagmus was present. At the age of 5 years his gait was unstable. A progressive myopathy ensued. Tests of pituitary reserve showed partial IGHD (8.2 ng/ml). Other pituitary hormones were within normal range. Muscle biopsy showed congenital myopathy of undefined etiology. MRI of the brain revealed the empty sella syndrome. Targeted resequencing with a panel containing probe sets for enrichment and analysis of > 4,800 clinically relevant genes, targeting 12Mb of the human genome revealed the c.250C>T (R84C) LHX4 mutation. His father is healthy, with no myopathy or pituitary deficiencies, but has the same LHX4 mutation. This report extends the range of phenotypes associated with LHX4 gene mutations. To the best of our knowledge, we are the first to report on congenital myopathy in an LHX4 gene mutation. Forthwith, we offer a comprehensive review of the patients published so far with their clinical and genetic characteristics.

Emanuel Syndrome (ES): new case-report and review of the literature

Multiple congenital anomalies and craniofacial dysmorphism are characterizing the so-called Emanuel or supernumerary der(22)t(11;22) syndrome (OMIM609029). Mental and developmental retardation are major clinical features. The der(22) may arise from a parental balanced t(11;22)(q23;q11.2) or can be created de novo. Here we present a 2 years old boy with normal prenatal history, cyanotic at delivery and with ear anomalies, a preauricular tag, high-arched palate and micrognathia. There were neither microcephaly, nor heart or kidney defects. Psychological and motor testing at the age of 2 years confirmed significant mental and developmental delay. In addition, the child had seizures and an abnormal electroencephalogram. Cytogenetic and molecular analyses revealed a karyotype 47,XY,+der(22)t(11;22)(q23;q11.2). As parents refused further tests it could not be determined if the der(22) arose de novo or was parentally derived. Overall the present report should alert physician to offer cytogenetic and/or molecular diagnostics in comparable cases.

Billateral polycystic kidneys in a girl with WAGR syndrome

The WAGR contiguous gene deletion syndrome is a combination of Wilms tumor, aniridia, genito-urinary abnormalities, and mental retardation. An 8.5-year-old girl was initially investigated at the age of 18 months for congenital bilateral aniridia, cataracts, glaucoma and epicantus. The ultrasound (US) scan showed polycystic kidney disease. FISH study revealed deletion of the WT1 and PAX6 gene in the 11p13 WAGR region. Forty days after the first kidney US, the second US revealed a 3 cm tumor in the right kidney: a Wilms tumour, treated successfully with the Wilm's tumor protocol. The authors conclude that the identification of the deletions in the WAGR region in patients with aniridia should definitely be done. In addition, Wilms tumor can have a very rapid growth, which, per se requires frequent and careful ultrasound kidney controls. Polycystic kidneys can be part of the WAGR presentation.

Rare diseases with renal involvement in the Republic of Macedonia

Rare diseases (RDs) pose a significant set of problems for patients, since their disease and general social and health situation are often not recognized by the medical community and shunned by health insurance. The sheer number of RDs (5000-8000) and the number of patients (6-8% of the population) are challenging for every society. We wanted to get a better understanding of the rare diseases affecting the kidneys and urinary tract (RDAKUT) in the Republic of Macedonia and we investigated principally the PubMed Central articles of Macedonian medical professionals dealing with RDAKUT, but we also used information on RDAKUT from local sources. A significant number of RDs have been published, demonstrating the awareness and skill of Macedonian medical professionals despite pretty limited diagnostic facilities. We still feel that RDAKUT are underdiagnosed (e.g. Fabry's disease has not yet been reported), and that many patients with RDs have a long way to go before an accurate diagnosis. Increased awareness and ameliorated education are needed by the physicians; while health insurance must include RDAKUT covering their diagnosis and treatment costs. Neonatal screening for ~30 diseases (instead of just hypothyroidism) is also required. Patients' organizations exist and they are active in promoting their interests before of the health authorities.

Congenital erythropoietic porphyria with two mutations of the uroporphyrinogen III synthase gene (Cys73Arg, Thr228Met)

Congenital erythropoietic porphyria (CEP) is an autosomal recessive inborn error of metabolism that results from the markedly deficient activity of uroporphyrinogen III synthase (UROS). We describe a 14-year-old girl with red urine since infancy, progressive blistering and scarring of the skin, and moderate hemolytic anemia. After years of skin damage, her face is mutilated; she has a bald patch on the scalp, hypertrichosis of the neck, areas of skin darkening, and limited joint movements of the hands. Total urine excretion and fecal total porphyrin were both markedly raised above normal levels. Sequencing of the UROS gene identified two mutations causing CEP (Cys73Arg, Thr228Met). The patient lesions are progressing. Bone marrow transplantation and/or gene therapy are proposed as the next steps in her treatment. In brief, we describe a CEP with confirmed two pathogenic mutations, severe phenotype and discuss the various treatment options available.

Early-onset ocular ochronosis in a girl with alkaptonuria (AKU) and a novel mutation in homogentisate 1,2-dioxygenase (HGD)

Alkaptonuria (AKU) is a disorder of phenylalanine/tyrosine metabolism due to a defect in the enzyme homogentisate 1,2-dioxygenase (HGD). This recessive disease is caused by mutations in the HGD gene. We report a 14-year-old girl who was referred after presenting black urine. Careful examination revealed ochronosis of the conjunctiva. There was no affection of the cardiac valves. Elevated excretion of homogentisic acid in urine was found. Sequence analysis of the HGD gene from genomic DNA revealed that the patient is a compound heterozygote with a previously described mutation (c.473C>T, p.Pro158Leu), and a novel one (c.821C>T, p.Pro274Leu). Her mother is heterozygous for the novel mutation, while the brother is heterozygous for the previously described mutation. In summary, we describe an alkaptonuric patient with ocular ochronosis and a novel HGD mutation, c.821C>T, p.Pro274Leu.

Acute Gallbladder Hydrops and Arthritis: unusual initial manifestations of Wilson's Disease (WD): Case Report

Wilson disease (WD) is an autosomal recessive disorder, in which copper is deposited in the liver, brain, cornea and kidneys. The clinical presentation is variable, with fully expressed disease manifesting cirrhosis, neurologic damage and Kayser-Fleischer (K-F) ring on the cornea. A 24-year-old patient developed right upper quadrant pain with a palpable mass and a swelling of the right talocrural articulation. X-rays were uneventful, but the routine examination of hepatic enzymes discovered a 6-8 fold increase in SGPT, SGOT and AST. Antibodies for hepatitis B, C were normal, as well as the ANA, ANCA, antimytochondrial and anti-smooth muscle antibodies. Ultrasound of the abdomen revealed extremely dilated hepatic, cystic ducts as well as gallbladder. A large, oedematous gallbladder with yellow green bile was removed, the liver was found to be cirrhotic, but as the operative bleeding was abundant a biopsy was not done. Serum ceruloplasmin was low [0.160 g/l (normal 0.204-0.407)], serum copper 12.7 µmol/l (11.0-24.4), transaminasis: always very high, in the last months normal/slightly elevated. Urine copper: 1.0 µmol/24 h (>9.44). As first seen the proband had tremor, dysarthria, dystonia and K-F ring on the cornea. After 10 months of treatment with penicillamine his transaminases normalized, the tremor, dysarthria, dystonia initially got worse and then ameliorated. The coagulation times are ameliorated, but not yet normalized. Mutational analysis has shown that the proband is homozygote for c.3207 C->A, p.H1069Q while his parents are heterozygotes. His sister is a healthy non-carrier. In brief, we describe an unusual presentation of WD, with gallbladder hydrops and talocrural arthritis in a patient with complete clinical manifestations of the disease.