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Many causes of thyroxine malabsorption are described in the literature, but the most common cause of failure of thyroxine therapy is poor patient compliance, or pseudomalabsorption. We describe the case of a female patient who underwent total thyroidectomy for Basedow-Graves disease. Post-operatively, several treatment regimens were employed to achieve euthyroidism, but only injectable thyroxine was found to be effective. To exclude levothyroxine malabsorption, the patient was hospitalized in a hypothyroid state while a single oral test dose of levothyroxine (1000 microg) was administered. Within 4 hours a decrease of TSH level (from 59.7 to 55.6 microUI/ml) and a significant increase in free T4 levels (from 0.8 to 15.5 pg/ml) was observed, eliminating a malabsorption problem. The cause of resistance to thyroid hormone therapy was poor patient compliance, leading to the designation of this as a case of pseudomalabsorption.

Acromegaly usually results from GH hypersecretion by a somatotroph adenoma. The fertility of acromegalic patients is often impaired. Several factors may impact the course of pregnancy in acromegaly. Disturbed pituitary function might lead to infertility or spontaneous abortion. GH is a powerful insulin antagonist, and pregnant acromegalic patients are prone to added glucose intolerance and diabetes. Pregnancy itself might also impact the course of the pituitary tumor. During pregnancy, the normal pituitary increases in size due to estrogens-mediated hyperplasia. Therefore, tumors are at risk for hemorrhage due to enhanced vascularity, and might compress the optic chiasm. In this article we summarize the data on the literature on the reciprocal influences between acromegaly and pregnancy, we discuss therapeutic options and advance diagnostic and surveillance schedules of acromegaly during pregnancy.

Multihormonal bilateral petrosal sinus sampling (BPSS) has been proposed to improve corticotroph microadenomas prediction of lateralisation. Few series have simultaneously compared data of pituitary MRI, surgical findings and multihormonal BPSS. Seven patients (6F/1M) with Cushing's disease, mean age at diagnosis of 35 years (range 24-55) were prospectively studied to compare radiological and multihormonal BPSS data with surgical and pathological findings. In untreated patients, simultaneous measures of ACTH, TSH and prolactine (PRL) were done at time 0, 7, 15, 22 minutes after CRH (500 microgram) and TRH (200 microgram) stimulation. An intersinus gradient of 1.4 was considered as a lateralisation. All microadenomas were identified during surgery, diameters ranged from 2 to 7 mm. All patients were in long-term surgical remission. Pathological studies confirmed a tumoral tissue with ACTH immunostaining in 6/7 cases and PRL in 3/7 cases. Pituitary MRI correctly identified tumors in 4 cases, the remaining tumors were not seen. Basal and stimulated intersinus gradients of ACTH, TSH and PRL were homolateral in 6/7 cases and were coincident with surgical findings in 4/7 cases. The other three cases were contralateral to MRI and surgical data. In conclusion, simultaneous gradient of ACTH, PRL and TSH did not improve lateralisation prediction in this series. Hormonal hypersecretion was homolateral in six cases whereas pathological studies demonstrated a mixed secretion in only three cases. A preferential pituitary draining could explain these discordances. Data from our series and from others (done with CRH stimulation and ACTH-PRL measures) strongly suggest a paracrine interaction between tumoral and normal pituitary tissue.

Multiple Endocrine Neoplasia type 1 (MEN 1) is an autosomal dominant syndrome characterized by neoplasia of the parathyroid glands, the endocrine pancreas and the anterior pituitary gland. Recently the identification on chromosome 11 (locus q13) of the gene responsible for MEN 1 has allowed direct genetic diagnosis of MEN 1-affected family members. To date almost 300 families have been described and genetically characterized. The genetic etiology of most pituitary tumours remains unknown. Pituitary adenomas can develop sporadically or as a part of multiple endocrine neoplasia type 1. In this review, the recently published data on the pathology of the MEN 1 syndrome will be summarized. The clinical, morphological and genetic aspects of sporadic and MEN 1-associated pituitary adenomas will be outlined.