Panhypopituitarism secondary to a macroprolactinoma manifesting with pancytopenia: case report and literature review

Haematological actions of androgens

In this review, we discuss the effects on androgens on the haemopoietic system, focussing largely on the effects of testosterone on erythropoiesis. Stimulation of erythropoiesis is one of the most consistent effects of testosterone treatment observed in clinical trials. In men with anaemia this effect can be beneficial. Conversely, erythrocytosis is one of the most common adverse effects of testosterone treatment with a relative risk of 8.14 (95% CI: 1.87-35.40) estimated by a recent meta-analysis of randomised placebo controlled clinical trials. A reduction in haemoglobin is commonly seen in men receiving androgen deprivation therapy for prostate cancer, and in transwomen receiving gender affirming therapy to reduce serum testosterone. While mechanisms by which androgens regulate erythropoiesis are not fully understood, it is likely that effects on erythropoietic progenitor cells and erythropoietin are involved, with secondary effects on iron metabolism. In contrast, whether androgens exert clinically relevant effects on white blood cells and on platelets requires further study.

Hormones and the bone marrow: panhypopituitarism and pancytopenia in a man with a pituitary adenoma

In rare cases, pancytopenia results from hormonal deficiencies that arise in the setting of panhypopituitarism. Here we describe the unusual case of a 60-year-old man who presented with progressive fatigue and polyuria, and whose laboratory workup revealed a deficiency of the five hormones associated with the action of the anterior pituitary (thyroid hormone, testosterone, cortisol, prolactin, and insulin-like growth factor-1). Imaging of the pituitary demonstrated a cystic mass consistent with a pituitary adenoma replacing much of the normal pituitary tissue. His symptoms and hematologic abnormalities rapidly resolved with prednisone and levothyroxine supplementation. While the majority of reported cases of panhypopituitarism with bone marrow suppression are the result of peripartum sepsis or hemorrhage leading to pituitary gland necrosis (Sheehan's syndrome), it is also important to consider the diagnosis of hypopituitarism in patients with hypothyroidism, low cortisol levels, and pancytopenia. The causal relationship between pancytopenia and panhypopituitarism is not well understood, though it does reinforce the important influence of these endocrine hormones on the health of the bone marrow.

Lack of TSH stimulation in patients with differentiated thyroid cancer - possible causes

Differentiated thyroid cancer is one of the most common endocrine cancers. Typical standard treatment includes total thyroidectomy with partial lymphadenectomy, then depending on the indications, treatment with iodine isotope 131-I. A prerequisite to conduct the therapy is to obtain endogenic thyroid-stimulating hormone (TSH) stimulation (TSH > 30 µU/ml). We describe two patients with differentiated thyroid carcinoma in whom no rise in serum TSH was observed after withdrawal of thyroxine. In one patient TSH deficiency was due to partial hypopituitarism secondary to a tumor of the pituitary gland. In the second patient the TSH level was suppressed by metabolically active thyroid tissue within bilateral ovarian teratomas. The problems with TSH growth after withdrawal of thyroxine requires additional studies to identify the cause. Above two possible reasons for the lack of TSH stimulation after withdrawal of thyroxine were presented. In the case of non-TSH stimulation due to hypopituitarism both control tests and isotope treatment should be carried out using stimulation by recombinant human TSH (rhTSH).