Two-step development of a pituitary adenoma: from hyperprolactinemic syndrome to Cushing's disease.

In this report we describe the case of a young female patient with amenorrhea-galactorrhea syndrome apparently due to pituitary PRL-secreting adenoma who, after three years of dopaminergic therapy without any shrinkage of the tumor, developed true Cushing's disease. Progression from hyperprolactinemia to hypersecretion of ACTH has been rarely described and it may be due to different possibilities. However, histopathological and immunohistochemical studies of the adenoma showed a pattern of PRL negative and ACTH positive cells, excluding mixed pituitary tumor. In order to explain the progression from hyperprolactinemia with amenorrhea-galactorrhea to an ACTH hypersecretion syndrome, it must be hypothesized either pituitary stalk compression or the influence of paracrine regulation factor(s) (such as Galanine) due to an "initially silent" corticotropinoma. This case confirms that the presence of hyperprolactinemia in a patient with pituitary tumor and amenorrhea-galactorrhea syndrome is insufficient to confidently conclude for prolactinoma. Furthermore, it underlines the importance both of clinically monitoring the patient with prolactin pituitary adenoma if dopaminergic therapy does not reduce tumor volume, and of accurately and repeatedly measuring the other pituitary hormonal secretions.

[Spontaneous staphylococcal abscess of psoas muscle]. / Ascesso stafilococcico spontaneo del muscolo psoas.

An abscess of the psoas muscle is a rare occurrence and pathogenetic interpretation usually proves difficult. Abscessing of the psoas may be due either to direct diffusion of infections of adjacent structure or to hematogenous spread. However, not uncommonly, a "spontaneous" abscess occurs, which cannot be correlated to other sites of infections or sepsis. The Authors describe two cases of abscesses of the psoas muscle following Staphylococcus aureus sepsis of unknown origin.

[Hyperparathyroidism due to parathyroid carcinoma located in the mediastinum]. / Iperparatiroidismo da carcinoma delle paratiroidi a sede mediastinica.

Parathyroid gland carcinoma is a rare cause of primary hyperparathyroidism. The authors discuss the case of a 56-year-old man who presented with hypercalcemia and multiple bone lesions suggestive of tumor metastases. Laboratory and radiological investigations revealed primary hyperparathyroidism in a patient with evidence of osteitis fibrosa cystica, sustained by carcinoma of a mediastinal parathyroid gland. Early titration of parathyroid hormone (PTH) levels in all patients with hypercalcemia of unclear cause is important for early diagnosis of cases that are tumor-sustained and prevention of the most severe complications. The role of immunostaining with anti-PTH antibodies in demonstrating parathyroid gland tissue in ectopic and/or non-functioning primary tumors, as well as metastases, is also discussed.