1/200. Pituitary deficiency and lack of gonads in an XY pseudohermaphrodite with beta 39/lepore haemoglobinopathy.We describe the occurrence of hypothyroidism and hypogonadotropic hypogonadism in an XY pseudohermaphrodite subject affected by beta-thalassemia. The patient, reared as female, diagnosed at 14 months of age as having a beta 39/Lepore hemoglobinopathy, treated with multiple transfusion therapy, was referred at age of 15 years because of delayed puberty. Complete endocrine evaluation showed low levels, both basal and after combined LHRH-TRH and hCG stimuli, of FSH, LH, TSH, estradiol (E2), testosterone (T), progesterone (P), androstenedione (A), and FT4 levels, and normal PRL, cortisol, 17OHP and ACTH levels. Imaging studies (ultrasound, magnetic resonance, radioisotope scanning and gonadal vessels phlebography) did not show internal genitalia and gonads. karyotype resulted 46,XY. PCR amplification of the SRY gene confirmed the presence of the y chromosome. female genitalia without uterus in a subject with y chromosome SRY gene, and no detectable testes indicate a condition of male pseudohermaphroditism associated with testicular regression. Low gonadotropin and sex steroid levels are suggestive of combined acquired hypothalamic-pituitary and gonadal impairment, due to iron deposition in both organs. We cannot exclude congenital failure of testosterone synthesis and action in this case, because lack of gonads is an unusual finding in thalassemic hypogonadic subjects.- - - - - - - - - - ranking = 1keywords = pituitary (Clic here for more details about this article) |
2/200. Primary hypothyroidism and pituitary insufficiency.A 40-year-old man with primary hypothyroidism and sellar enlargement is described. There was deficiency of all pituitary tropic hormones except TSH which was elevated. TRH stimulation revealed responsiveness of pituitary thyrotropic cells, and thyroxine administration suppressed the elevated TSH. These findings are compatible with either a TSH-producing chromophobe adenoma resulting from primary hypothyroidism or, because of the suppressibility of the TSH secretion, thyrotropic hyperplasia secondary to hypothyroidism maintaining TSH secretion in the face of a non-TSH-secreting pituitary tumor.- - - - - - - - - - ranking = 7keywords = pituitary (Clic here for more details about this article) |
3/200. Inefficiency of the anticoagulant therapy in the regression of the radiation-induced optic neuropathy in Cushing's disease.radiation-induced optic neuropathy is a rare complication (prevalence less than 1%) following radiotherapy of the sellar region. However, the vasculopathy in Cushing's disease predisposes to radiation-induced injury. We report the case of a 24-year-old man with Cushing's disease since he was 16. The hormonal study including bilateral inferior petrosal sinus catheterization diagnosed a pituitary right lesion, but imagiology was always negative. He underwent a transsphenoidal microadenomectomy and the pathological study showed the presence of corticotrophic hyperplasia but no adenoma. Secondary hypothyroidism and hypogonadism as well as permanent diabetes insipidus were diagnosed and because the patient was not cured he underwent a second transsphenoidal total hypophysectomy. After that and because he was still hypercortisolemic, pituitary external irradiation was given in a total dose of 6000 rad. Six months later he developed progressive bilateral visual loss. Cerebral MR revealed focal enhancement of the enlarged optic nerves and chiasm, associated with demyelination areas of the posterior visual pathways. Treatment was tried first with high doses of corticosteroids and later with anticoagulants-heparin EV. 1000 U/h during 7 days followed by warfarin, but unsuccessfully, probably because the patient was already amaurotic at the beginning of the last treatment.- - - - - - - - - - ranking = 2keywords = pituitary (Clic here for more details about this article) |
4/200. Thyroid hemiagenesis and elevated thyrotropin levels in a child with williams syndrome.A girl with williams syndrome (WS) presented with elevated thyrotropin (TSH) levels (7.0 microU/ml), normal free thyroid hormone concentrations, and absent antithyroid autoantibodies. Thyroid ultrasonography and scintigraphy showed hemiagenesis of the left lobe and no evidence of ectopic tissue. TSH response to thyrotropin-releasing hormone (TRH) injection (200 microg/mq, i.v.) was exaggerated and prolonged, suggesting subclinical hypothyroidism. The biological activity of circulating TSH was slightly below the normal range [TSH bioactivity (B) to immunoreactivity (I) ratio (TSH B/I) = 0.4, normal: 0.6-2.2]. These abnormalities are similar to those seen in patients with hypothalamic hypothyroidism. Thyroid function is not a recognized manifestation of WS and is not routinely investigated. However, abnormalities of the hypothalamic-pituitary-thyroid (HPT) axis and thyroid dysgenesis have been found in other WS cases. Genes mapping at 7q11.23, contiguous to the chromosomal region deleted in most WS patients, may be involved in the development of the thyroid gland, contributing to the complex phenotype of WS.- - - - - - - - - - ranking = 1keywords = pituitary (Clic here for more details about this article) |
5/200. A case of congenital hypopituitarism: difficulty in the diagnosis of ACTH deficiency due to high serum cortisol levels from a hypothyroid state.A three-month-old boy presented congenital hypopituitarism in which the hypothyroid state masked ACTH deficiency. Multiple anterior pituitary hormone deficiencies, including ACTH, were finally confirmed. High basal serum cortisol levels (up to 45.1 microg/dl) were observed during a stressful episode before L-thyroxine replacement therapy was started. Decreased morning serum cortisol levels (5.0 microg/dl or below) were observed on the sixth day of L-thyroxine replacement therapy despite mild hypoglycemia (lowest serum glucose level of 50 mg/dl). ACTH deficiency was then confirmed by insulin-induced hypoglycemia test (peak serum cortisol level of 4.9 microg/dl). The present findings showed that serum cortisol levels can be high during a stressful episode in an infant with ACTH deficiency and a coexisting hypothyroid state. Thus, the diagnostic evaluation of adrenal function soon after L-thyroxine replacement therapy is important in order to verify a possible subclinical ACTH deficiency, even in the presence of high serum cortisol levels before L-thyroxine replacement therapy.- - - - - - - - - - ranking = 9.1788203068265keywords = anterior pituitary, hypopituitarism, pituitary (Clic here for more details about this article) |
6/200. Primary hypothyroidism-associated TSH-secreting pituitary adenoma/hyperplasia presenting as a bleeding nasal mass and extremely elevated TSH level.A 41-year-old male with primary hypothyroidism and a huge TSH-secreting pituitary tumor presented with a bleeding nasal mass that was initially misdiagnosed as a paraganglioma. Other unique features of the case include lack of complaints related to hypothyroidism, an extremely elevated TSH level of 3474 mU/l, and a low prolactin level. The presence of primary hypothyroidism made differentiating TSH-secreting pituitary adenoma from secondary thyrotroph hyperplasia difficult. A low molar ratio of alpha-subunit to TSH on presentation, together with normalization of TSH level and a 50% reduction in the size of the tumor after 6 weeks of thyroxine replacement therapy, suggested the presence of thyrotroph hyperplasia. However, the lack of further decrease in the size of the tumor that was associated with increased metabolic activity on 18-FDG PET scan, intense uptake on octreotide scan, and an elevated alpha-subunit to TSH molar ratio despite the normalization of free T4 and TSH levels for 16 months suggested the coexistence of thyrotroph adenoma. Together, the findings support the view that thyrotroph adenoma/irreversible hyperplasia can result from long standing primary hypothyroidism.- - - - - - - - - - ranking = 6keywords = pituitary (Clic here for more details about this article) |
7/200. Severe congenital hypothyroidism due to a homozygous mutation of the betaTSH gene.Isolated TSH deficiency leading to hypothyroidism seems to be a rare condition, escaping the diagnosis by neonatal screening programs, which are based on the primary determination of TSH. This is the first report of a case with an autosomal recessive TSH defect caused by a homozygous mutation of the betaTSH gene that was diagnosed in the early neonatal period. Hypothyroidism in the first child of apparently unrelated parents was suspected because of the classical symptoms of congenital hypothyroidism, which were fully expressed already on the 11th day of life. Routine neonatal TSH-screening on the 4th day of life had been normal, but subsequent determination of serum thyroid hormone levels revealed almost undetectable levels and thyroid hormone substitution was immediately started. Because there was no indication for other pituitary hormone deficiencies, sequence analysis of the betaTSH gene was initiated. A homozygous T deletion in codon 105 was found resulting in a change of a highly conserved cysteine to valine followed by eight altered amino acids and a premature stop codon due to the frame-shift. This altered betaTSH is a biologically inactive peptide. Because of the early development of severe symptoms, it is possible that this altered TSH suppresses the physiologic constitutive activity of the unliganded TSH receptor. Rapid molecular diagnosis in this patient clarified the diagnosis without additional endocrine and imaging studies and it is concluded, that symptoms of hypothyroidism in the neonatal period should result always in an immediate comprehensive work-up of thyroid function including molecular genetic studies irrespective of the screening result.- - - - - - - - - - ranking = 1keywords = pituitary (Clic here for more details about this article) |
8/200. Pituitary hyperplasia resulting from primary hypothyroidism mimicking macroadenomas.Three patients presented with clinical and imaging features suggestive of a primary functional pituitary adenoma. Surprisingly, thyroid function testing revealed co-existing primary hypothyroidism. The pituitary tumours represented hyperplasia of anterior pituitary thyrotrophs secondary to hypothyroidism. Complete regression was achieved with thyroxine replacement therapy. Careful attention should be paid to differentiating this condition from prolactinoma or the rare TSH producing adenoma.- - - - - - - - - - ranking = 5.0786546576351keywords = anterior pituitary, pituitary (Clic here for more details about this article) |
9/200. Panhypopituitarism associated with diabetes insipidus in a girl with a suprasellar arachnoid cyst.We report on a female patient with a large suprasellar arachnoid cyst (3.5 x 2.5 cm) combined with right optic nerve hypoplasia. She developed growth hormone deficiency and hypothyroidism at the age of 8.5 years, adrenal insufficiency at the age of 11 years, diabetes insipidus and hypogonadotropic hypogonadism at the age of 15 years. When last seen at the age of 19 years she was extremely obese ( 5.9 BMI SDS). The endocrine picture suggests that arachnoid cysts might be involved in far more complex hypothalamic-pituitary disturbances than previously thought.- - - - - - - - - - ranking = 5.8801325193531keywords = hypopituitarism, pituitary (Clic here for more details about this article) |
10/200. Transdifferentiation of somatotrophs to thyrotrophs in the pituitary of patients with protracted primary hypothyroidism.In patients with protracted primary hypothyroidism, the pituitary is enlarged due to the lack of feedback inhibition by thyroid hormone. In the present work, adenohypophysial biopsies from three women with protracted primary hypothyroidism were investigated by routine histology, immunocytochemistry, double immunostaining, immunoelectron microscopy, and combined immunocytochemistry - in situ hybridization. These methods confirmed the presence of massive thyrotroph hyperplasia and the formation of "thyroidectomy" or "thyroid deficiency" cells. A number of thyroidectomy cells were found to be immunoreactive for growth hormone (GH). Double immunostaining and immunoelectron microscopy revealed the presence of bihormonal cells containing both GH and thyroid stimulating hormone (TSH). Immunostaining combined with in situ hybridization revealed GH immunoreactive cells expressing TSH mRNA as well as TSH immunopositive cells expressing GH mRNA. Our findings provide conclusive evidence that somatotrophs may transform to thyrotrophs. Thus, in addition to multiplication of thyrotrophs, transdifferentiation of GH cells to thyrotrophs contributes to the increase of TSH-producing cells. The presence of such bihormonal cells best termed "thyrosomatotrophs" supports the concept that adenohypophysial cells are not irreversibly committed to the production of one single hormone and that their phenotype can change in response to functional demand.- - - - - - - - - - ranking = 5keywords = pituitary (Clic here for more details about this article) |
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