Endocrine Abstracts

A lot of chromomosomal abnormalities have been described of which some are very unusual. Mosaicism refers to a condition where chromosomal (abnormalities) altered structure or number of chromosomes are present in some but not all cells. Polyploidy is defined as a condition where cells contain more than two homologous sets of chromosome, due to fertilization abnormalities; tetraploidy rarely allows birth of a living child but accounts for 6% of spontaneaous abortion.

We report the case of a 35-year-old woman suffering from severe obesity treated by bariatric surgery; she complained of dizziness attributed to a reactive hypoglycaemia. She had a complex medical history including idiopathic hyperprolactinemia and spaniomenorrhea treated by cabergoline, hypothyroidism treated with levothyroxine, arterial hypertension associated with hypokalemia, bilateral cataract, right carpal tunnel syndrome, patent ductus arteriosus requiring surgery at the age of 14, removal of nevi, papillary malformation and iris muscle dysfunction. Her weight was 106 kg, her height 151 cm. On examination, she presented with a shortened 4th metarcarpal bone, a moderately ogival palate, a short neck and multiple nevi throughout the body. Biologically, no evidence for reactive hypoglycaemia or hyperalmdosteronism was found. Karyotype was normal (46,XX). After stopping hypnotic treatment (antidepressants) and cabergoline, prolactin level was normal but there was a GH deficiency as evidenced by a low IGF-1 level and a GH peak <2 mU/L after stimulation. Finally, a mosaicism was found on karyotyping a cutaneous biopsy showing both diploid and tetraploid (28%) cells (46,XX/92,XXXX).

Tetraploidy is caused by a mitotic failure during the early stage of zygotic development. Mosaicism is responsible for a great number of congenital abnormalities and a wide range of mental and growth retardation. Currently, fourteen cases have been reported in the literature: five patients deceased in the early life and the older living patient is 21 years of age.