Infantile malignant osteopetrosis: a rare cause of neonatal hypocalcemia

Infantile malignant osteopetrosis (IMO; OMIM 259700) is a rare inherited bone disease characterized by reduced or dysregulated activity of osteoclasts, resulting in generalized osteosclerosis. The disease usually presents within the first few months of life with anemia, hepatosplenomegaly, frontal bossing, nystagmus, blindness, deafness, and bone fractures. Children with IMO are at risk of developing hypocalcemia, with attendant tetanic seizures. We report the case of a baby boy who presented with neonatal hypocalcemia. Skeletal radiographs demonstrated sclerotic bones and a dense base of the skull with typical "space alien" face confirming the diagnosis of IMO. Pancytopenia developed at 2 months of age. Visual evoked potential showed severe bilateral optic nerve damage. Genetic mutation study revealed a new mutation in exon 13 of the TCIRG1 gene. Neonatal hypocalcemia can occur as result of IMO, which is easily missed out by clinicians. This causes delay in establishing the diagnosis and starting necessary treatment. Therefore, osteopetrosis should be kept in mind as a rare cause of neonatal hypocalcemia.

Is basal serum 17-OH progesterone a reliable parameter to predict nonclassical congenital adrenal hyperplasia in premature adrenarche?

To determine the critical features for the diagnosis of nonclassical 21 hydroxylase deficiency (NC210HD) without performing adrenocorticotropic hormone (ACTH) test, we studied 186 cases with premature adrenarche. Clinical and laboratory features as well as basal 17-hydroxyprogesterone (17-OHP) were analyzed to determine factors important for differentiating NC21OHD. Overall, 6 patients (3.2%) had ACTH-stimulated 17-OHP > 10 ng/ml. A cutoff level of 2 ng/ml for basal 17-OHP was 66.7% sensitive and 78% specific for NC21OHD; however, a cutoff level of 1.55 ng/ml had higher sensitivity (83%) and specificity (70.6%). A cutoff of 1.55 ng/ml would lead to 31% of cases with premature adrenarche having to undergo ACTH test, and only one case would have been missed. That case had a bone age SDS > 2. Three cases out of five with a basal 17-OHP > 5 ng/ml had stimulated 17-OHP < 10 ng/ml. A cutoff of 1.55 ng/ml for basal 17-OHP together with bone SDS > 2 in those with lower basal levels as a guide for carrying out an ACTH test may yield better results in the diagnosis of NC21OHD in the premature adrenarche population. A cutoff of 5 ng/ml for basal 17-OHP should not be used for diagnosis of NC21OHD.

Two pediatric patients with Von Hippel-Lindau disease type 2b: from patient to screening, from screening to patient

Von Hippel-Lindau (VHL) disease is an autosomal dominantly inherited tumor susceptibility disease characterized by the development of hemangioblastomas of the brain, spinal cord and retina; pheochromocytomas and renal cell carcinoma. The disease is caused by mutations in the VHL tumor suppressor gene located on chromosome 3p26-p25. In this paper, we present two patients with VHL disease type 2B confirmed by genetic analysis. Diagnosis in the first patient was based on demonstration of retinal hemangioblastoma in association with bilateral pheochromocytoma. Family screening revealed renal cell carcinoma in her father and uncle. The second patient was discovered during family screening of another index case in adult age. VHL disease should be clinically suspected in any individual with a pheochromocytoma especially when there is bilateral and/or multifocal disease or family history. Screening of patients and at-risk family members for VHL-associated tumors should be essential in management of VHL.

Growth hormone deficiency due to traumatic brain injury in a patient with X-linked congenital adrenal hypoplasia

X-linked adrenal hypoplasia congenita (AHC) is characterized by primary adrenal insufficiency and is frequently associated with hypogonadotropic hypogonadism (HH). The production of other pituitary hormones (adrenocorticotropic hormone [ACTH], growth hormone [GH], thyroid-stimulating hormone [TSH], and prolactin [PRL]) is usually normal. Mutations of the DAX-1 gene have been reported in patients with AHC and HH. We present a 13-year-old male patient with AHC caused by a nonsense mutation in the DAX-1 gene who developed GH deficiency following head trauma. He showed signs of adrenal insufficiency at the age of 23 months, and glucocorticoid and mineralocorticoid treatment was started. His parents reported head trauma due to a traffic accident at the age of 21 months. Adrenal computed tomography revealed hypoplasia of the left and agenesis of the right adrenal gland. Decreased growth rate was noted at the age of 12.5 years while receiving hydrocortisone 15 mg/m2/day. His height was 139.9 cm (-1.46 SD), body weight was 54.9 kg, pubic hair was Tanner stage 1, and testis size was 3 ml. His bone age was 7 years. His gonadotropin (follicle-stimulating hormone [FSH], luteinizing hormone [LH]) and testosterone levels were prepubertal. The evaluation of GH/insulin-like growth factor-1 (IGF-1) secretion at the age of 13 years revealed GH deficiency. Pituitary magnetic resonance imaging demonstrated a hypoplastic hypophysis (< 2.5 mm) and a normal infundibulum. GH treatment (0.73 IU/kg/week) was started. This paper reports a patient with genetically confirmed AHC demonstrating GH deficiency possibly due to a previous head trauma. Complete pituitary evaluation should be performed in any child who has survived severe traumatic brain injury.

Treatment of autonomous ovarian follicular cyst with long-term anastrozole therapy

Functional follicular ovarian cysts are frequently reported in girls with peripheral precocious puberty (PP). These cysts are usually self-limiting and resolve spontaneously. Several drugs like antiestrogens (tamoxifen) and new aromatase inhibitors are seldom used for treatment. Here we report a girl with peripheral PP who presented with unilateral enlargement of the ovary and a recurrent autonomous ovarian cyst. No skin pigmentation or bone anomaly was noted. The patient was successfully treated with anastrozole, a highly selective aromatase inhibitor. No adverse reaction was noted. Anastrozole is a safe and tolerable drug especially used to suppress estrogen action.

Evaluation of glucose homeostasis in transfusion-dependent thalassemic patients

Diabetes is an important problem encountered in thalassemic patients. The severity and type of glucose disturbances vary greatly in different studies. Also the pathogenesis seems to be complex; either insulin deficiency or insulin resistance may mediate the glucose disturbances. In a group of thalassemic patients glucose homeostasis was evaluated. Diabetes prevalence was 1.8%. Forty patients were investigated both with an oral glucose tolerance test and first-phase insulin response. Three patients had impaired fasting glucose, 1 patient had impaired glucose tolerance, and 2 patients had hyperinsulinism. Nineteen of 40 patients who were tested had low first-phase insulin response (47.5%) with below 10th centile. Age, BMI, height SDS, age at diagnosis, age at first blood transfusion, number of blood transfusions in a year, percentage of elevated liver enzyme, and hemoglobin and ferritin levels were not different between patients with low first-phase insulin response to patients with normal first-phase insulin response. Four patients are HCV infected, and only 1 of them had low first-phase insulin response. The study group showed a high rate of impairement in insulin secretion by first-phase insulin response to glucose overload, despite the low rate of insulin resistance. Defect of insulin secretion in thalassemic patients may develop earlier than insulin resistance, and then be accompanied by insulin resistance. Increasing insulin resistance with age and the occurrence of additional factors could lead to detoriation of glucose metabolism.

Approach in an adolescent Proteus male patient with megafoot

Proteus syndrome is a rare overgrowth syndrome characterized by hemihypertrophy, lower limb asymmetry, hyperpigmentations, lipomas, and vascular malformation. In this paper, we present a new adolescent Proteus syndrome patient with bilateral megafoot. He was very successful in playing football and was very popular among his friends. We present this case for the psychological and surgical aspects of this very interesting entity. We also review the recent literature related with Proteus syndrome.

Bilateral periventricular nodular heterotopia, severe learning disability, and epilepsy in a male patient with 46,XY,der(19)t(X;19) (q11.1-11.2;p13.3)

Periventricular nodular heterotopia (PNH) is a rare neuronal migration disorder in which immature neurons fail to undergo a directed migration from the ventricular and subventricular zones to the cerebral cortex. Classic PNH occurs predominantly in females and is associated with periods of epilepsy and near-normal intelligence. One gene associated with PNH was mapped to chromosome Xq28. PNH with learning disability is reported in 15 male patients with several syndromes and various congenital abnormalities such as craniosynostosis, frontonasal malformation, and agenesis of the corpus callosum. We present a 26-year-old male patient who was followed up with the diagnosis of epilepsy from the age of 1 year. Additionally the patient had severe learning disability, obesity, and hypogonadism. Imaging of his brain demonstrated PNH. Klinefelter syndrome was clinically suspected, and analysis of his chromosomes revealed a karyotype 46,XY,der(19)t(X;19) (q11.1-11.2;p13.3). Molecular techniques, such as subtelomere-specific fluorescent in-situ hybridization and multicolour banding, were also used. The same translocation was demonstrated in his mother and his maternal grandmother. This family might help to explain the gene localization of X-linked recessive PNH. In our patient, PNH is associated with familial (X;19) translocation. To our knowledge, this unique combination has not been reported in the medical literature.

The t(4;8) is mediated by homologous recombination between olfactory receptor gene clusters, but other 4p16 translocations occur at random

The t(4;8)(p16;p23) is the second most common constitutional chromosomal translocation and is caused by an ectopic meiotic recombination between the olfactory receptor gene clusters (ORGC), located on chromosome 4p and 8p. Given that ORGCs are scattered across the genome and make-up about 0.1% of the human genome we reasoned that translocations between 4p16 and other chromosomes might be mediated by ectopic recombination between different ORGC. In 13 patients, we mapped the breakpoints of either a balanced or unbalanced translocation between chromosome 4p16 and different chromosomes. For all four t(4;8) cases, the breakpoints fall within the 4p and 8pter ORGC, confirming that non-allelic homologous recombination (NAHR) between the ORGC is the main mechanism of the t(4;8) formation. For the nine other translocations, the breakpoints on chromosome 4 mapped to different loci, one of them within the ORGC and in two flanking the ORGC. In these three cases, the translocation breakpoint at the reciprocal chromosome did not contain ORGC sequences. We conclude that only the t(4;8) is mediated by NAHR between ORGC.

31 cases with oculoauriculovertebral dysplasia (Goldenhar syndrome): clinical, neuroradiologic, audiologic and cytogenetic findings

Goldenhar syndrome (GS) or oculoauriculovertebral dysplasia (OAVD) is characterized by pre-auricular skin tags, microtia, facial asymmetry, ocular abnormalities and vertebral anomalies of different size and shape. The phenotypical findings of this syndrome are variable due to heterogenous aetiology. For that reason, the physician sometimes faces difficulty when making a definite diagnosis of OAVD. We reviewed the clinical and laboratory findings of 31 patients (15 boys and 16 girls) aged from 1 day to 16 years with the clinical diagnosis of GS. The characteristic features were pre-auricular skin tags (90%), microtia (52%), hemifacial microsomia (77%) and epibulbar dermoids (39%). Vertebral anomalies were noted in 70% of the patients. Cardiac malformations were found in 39% while a genitourinary anomaly was noted in 23% and various central nervous system malformations in 47%. There were 3 pregnancies following an intracytoplasmic sperm injection (ICSI) technique among the 31 patients. Two patients with GS came from the same family. Their relatives had hydrocephaly, myelomeningocele and neural tube defects. It is known that some chromosomal aberrations are seen in GS. We performed chromosome analysis of 29 patients. Among these cases, only one patient with severe mental and motor retardation had a 47,XX,+der(22)t(11,22)(q23; q11 karyotype due to a maternal balanced translocation t(11;22)(q23;q11). This translocation was demonstrated in her sister, brother and maternal uncle. Additionally CATCH 22 analysis in 13 cases with OAVD with a CATCH 22 phenotype revealed no deletion. OAVD patients present with different morphologic features and systemic manifestations. A multidisciplinary approach should be undertaken by departments such as pediatric cardiology, audiology, ophthalmology and plastic surgery when evaluating patients with OAVD. Chromosome analysis should be performed in every patient with Goldenhar syndrome.

Partial trisomy (11;22) syndrome with manifestations of Goldenhar sequence due to maternal balanced t(11;22)

Here we report a 15-year-old girl patient who had severe mental and growth retardation, cleft palate, hemifacial microsomia, skin tags, hypoplasia of the external auditory canal, scoliosis and renal agenesis. Our patient was the fourth child of nonconsanguineous marriage. Peripheral blood chromosomal analysis of the patient revealed 47,XX,+der(22)t(11;22)(q23;q11). The maternal karyotype was reported as 46,XX,t(11;22)(q23;q11). Maternal balanced translocation t(11;22)(q23;q11) causing Goldenhar syndrome with 47,XX,+der(22) has not been reported previously. The presented case clearly indicates that in every case with Goldenhar syndrome, chromosome analysis should be done for the possibility of unbalanced translocations.

Ring chromosome 4 and Wolf–Hirschhorn syndrome (WHS) in a child with multiple anomalies

We report on a 16-month-old male patient with ring chromosome 4 and deletion of Wolf-Hirschhorn syndrome (WHS) region with multiple congenital anomalies including unilateral cleft lip and palate, iris coloboma, microcephaly, midgut malrotation, hypospadias, and double urethral orifices. Peripheral chromosome analysis of the patient showed 46,XY,r(4)(p16.3q35) de novo. Multicolor fluorescence in situ hybridization (FISH) study was also performed and according to multicolor banding (MCB) a r(4)(::p16.3 --> q34.3 approximately 35.1::) was found in all metaphases. Subtelomeric 4p region, subtelomeric 4q region, as well as, Wolf-Hirschhorn critical region were deleted in ring chromosome 4. Genomic microarray analysis was also performed to delineate the size of deletion. Cranial magnetic resonance imaging (MRI) showed hypoplastic corpus callosum, delayed myelinization, and frontal and occipital lobe atrophies. Both maternal and paternal chromosomal analyses were normal. We compare the phenotypic appearance of our patient with the previously reported 16 cases of ring chromosome 4 in the medical literature.