DiGeorge anomaly in a patient with isochromosome 18p born to a diabetic mother

Hypoparathyroidism: Genetics and Diagnosis

This narrative report summarizes diagnostic criteria for hypoparathyroidism and describes the clinical presentation and underlying genetic causes of the nonsurgical forms. We conducted a comprehensive literature search from January 2000 to January 2021 and included landmark articles before 2000, presenting a comprehensive update of these topics and suggesting a research agenda to improve diagnosis and, eventually, the prognosis of the disease. Hypoparathyroidism, which is characterized by insufficient secretion of parathyroid hormone (PTH) leading to hypocalcemia, is diagnosed on biochemical grounds. Low albumin-adjusted calcium or ionized calcium with concurrent inappropriately low serum PTH concentration are the hallmarks of the disease. In this review, we discuss the characteristics and pitfalls in measuring calcium and PTH. We also undertook a systematic review addressing the utility of measuring calcium and PTH within 24 hours after total thyroidectomy to predict long-term hypoparathyroidism. A summary of the findings is presented here; results of the detailed systematic review are published separately in this issue of JBMR. Several genetic disorders can present with hypoparathyroidism, either as an isolated disease or as part of a syndrome. A positive family history and, in the case of complex diseases, characteristic comorbidities raise the clinical suspicion of a genetic disorder. In addition to these disorders' phenotypic characteristics, which include autoimmune diseases, we discuss approaches for the genetic diagnosis. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Tetrasomy 18p: case report and review of literature

Tetrasomy 18p syndrome (Online Mendelian Inheritance in Man 614290) is a very rare chromosomal disorder that is caused by the presence of isochromosome 18p, which is a supernumerary marker composed of two copies of the p arm of chromosome 18. Most tetrasomy 18p cases are de novo cases; however, familial cases have also been reported. It is characterized mainly by developmental delays, cognitive impairment, hypotonia, typical dysmorphic features, and other anomalies. Herein, we report de novo tetrasomy 18p in a 9-month-old boy with dysmorphic features, microcephaly, growth delay, hypotonia, and cerebellar and renal malformations. We compared our case with previously reported ones in the literature. Clinicians should consider tetrasomy 18p in any individual with dysmorphic features and cardiac, skeletal, and renal abnormalities. To the best of our knowledge, we report for the first time an association of this syndrome with partial agenesis of cerebellar vermis.

Tetrasomy 18p: report of the molecular and clinical findings of 43 individuals

Thus far, the phenotype of tetrasomy 18p has been primarily delineated by published case series and reports. Findings reported in more than 25% of these cases include neonatal feeding problems, growth retardation, microcephaly, strabismus, muscle tone abnormalities, scoliosis/kyphosis, and variants on brain MRI. Developmental delays and cognitive impairment are universally present. The purpose of this study was to more fully describe tetrasomy 18p at both the genotypic and the phenotypic levels. Array CGH was performed on 43 samples from individuals with tetrasomy 18p diagnosed via routine karyotype. The medical records of 42 of these 43 individuals were reviewed. In order to gain additional phenotypic data, 31 individuals with tetrasomy 18p underwent a series of clinical evaluations at the Chromosome 18 Clinical Research Center. Results from the molecular analysis indicated that 42 of 43 samples analyzed had 4 copies of the entire p arm of chromosome 18; one individual was also trisomic for a section of proximal 18q. The results of the medical records review and clinical evaluations expand the phenotypic description of tetrasomy 18p to include neonatal jaundice and respiratory distress; recurrent otitis media; hearing loss; seizures; refractive errors; constipation and gastroesophageal reflux; cryptorchidism; heart defects; and foot anomalies. Additional findings identified in a small number of individuals include hernias, myelomeningocele, kidney defects, short stature, and failure to respond to growth hormone stimulation testing. Additionally, a profile of dysmorphic features is described. Lastly, a series of clinical evaluations to be considered for individuals with tetrasomy 18p is suggested.

Uveitis in DiGeorge syndrome: a case of autoimmune ocular inflammation in a patient with deletion 22q11.2

PURPOSE

Del22q11.2, also known as DiGeorge syndrome, has a spectrum of ocular, facial and systemic features. Despite features of T cell dysfunction, infection and autoimmunity (including juvenile idiopathic arthritis), uveitis has not been described in patients with DiGeorge syndrome.

METHODS

We describe a case of a 25-year-old male with bilateral granulomatous panuveitis who after initial investigation and treatment for an infectious cause was determined to have autoimmune-related uveitis with evidence on clinical, laboratory and imaging assessments suggestive of ocular sarcoidosis.

RESULTS

The patient was found to have a normal T cell count and T cell proliferative response that was compared to a control patient, and phenotypes determined by flow cytometry were normal. However, the CD4/CD8 ratio in this patient was slightly lower than normal and the number of CD28 negative T cells, in both CD4 and CD8 populations, were significantly higher than a control.

CONCLUSIONS

The significance of these T cell abnormalities is unknown in the context of this patient's uveitis but is suggestive of a role in autoimmunity, which is a known phenomenon in del22q11.2 syndrome, although autoimmune-related uveitis is not a previously described feature.

Infrequently studied congenital anomalies as clues to the diagnosis of maternal diabetes mellitus

The aim of this study was to identify congenital anomalies (CA) among infants of women with diabetes mellitus (DM) that, even though infrequent or infrequently reported, may suggest diabetic teratogenesis. Using 1976-2005 data from the Spanish Collaborative Study of Congenital Malformations (ECEMC), we compared the frequency of selected CA among 130 infants with CA born to women with pregestational DM (PGDM) and 30,009 infants with CA whose mothers had normal glucose tolerance (NGT). To identify which CA were not only significantly more frequent among infants of mothers with PGDM, but also more specific, we calculated the quotient of their frequencies (frequency ratio: FR). The same analysis was made using data from 927 infants of mothers with gestational DM (GDM). Among the studied defects, several were statistically significantly more frequent among infants of PGDM mothers than among infants of mothers with NGT, although the specificity of their association with DM varied, as indicated by the values of the FR. These included: anorectal atresia/stenosis (FR = 2.81; P = 0.03), hallucal polydactyly (FR = 3.62; P = 0.002), heterotaxy (FR = 5.70; P = 0.049), hypertrophic cardiomyopathy (HCM) (FR = 61.60; P = 0.000000), multicystic dysplastic kidneys (MDK) (FR = 5.13; P = 0.0002), and thymus aplasia/hypoplasia (FR = 29.62; P = 0.000001). The only CA significantly more frequent among infants of women with GDM were HCM (FR = 8.60; P = 0.002) and MDK (FR = 1.80; P = 0.01). Our results suggest that maternal PGDM should be suspected in children with hallucal polydactyly, anorectal atresia/stenosis, heterotaxy, or aplasia/hypoplasia of the thymus. The presence of transient HCM or MDK in a newborn suggests maternal PGDM or GDM. These observations are important in view of the increasing worldwide frequency of DM and the high proportion of individuals with DM in whom the condition remains undiagnosed. (c) 2007 Wiley-Liss, Inc.