INTRODUCTION: Unexplained anaemia is a rare mode of presentation for 
prolactinoma. We describe a case of a man, with chronic anaemia ascribed to old 
age. Six years later, he was evaluated and diagnosed with a prolactinoma and 
resultant osteoporosis. Prolactinoma in old people may present insidiously with 
chronic anaemia and osteoporosis with or without sexual dysfunction.
CASE PRESENTATION: We describe the case of a 70-year-old Caucasian man who 
presented with mild anaemia and tiredness. His anaemia was investigated and 
ascribed to senescence. Endocrine causes were not considered or tested for. Six 
years later, he was again referred. Reassessment and direct questioning revealed 
long-standing sexual dysfunction. It was also discovered that our patient had 
fractured his radius twice, with minor trauma, during the preceding year. His 
serum prolactin was massively increased and a magnetic resonance imaging (MRI) 
scan of the head demonstrated a pituitary mass consistent with a prolactinoma. 
Dual X-ray absorptiometry revealed osteoporosis. Treatment of the prolactinoma 
led to a reduction in his serum prolactin with a rise in his haemoglobin to 
normal levels. This suggested that the prolactinoma was present during the 
initial presentation and was the cause of his anaemia.
CONCLUSION: This case highlights the importance of fully evaluating and 
investigating unexplained anaemia in older people and that endocrine causes 
should be considered. Osteoporosis also requires evaluation with secondary 
causes considered.