Lymphocytic hypophysitis in nonpregnant middle-aged females mimicking pituitary adenoma

S Sankhe¹, J Gandhi¹, NS Shah², S Khare²,  
¹ Department of Radiology, Seth GS Medical College and King Edward Memorial Hospital (KEM) Hospital, Mumbai, Maharashtra, India
² Department of Endocrinology, Seth GS Medical College and King Edward Memorial Hospital (KEM) Hospital, Mumbai, Maharashtra, India

Correspondence Address:
J Gandhi
Department of Radiology, Seth GS Medical College and King Edward Memorial Hospital (KEM) Hospital, Mumbai, Maharashtra
India

Full Text

Sir,

This letter pertains to the original letter to the editor "Lymphocytic hypophysitis in nonpregnant middle-aged female mimicking pituitary adenoma" by Gulwani et al. [1] We would further like to point out some more diagnostic features to accurately diagnose lymphocytic hypophysitis (LYH).

In LYH, there can be symmetric or asymmetric enlargement and homogeneous or heterogeneous enhancement of the pituitary gland. [2] Moreover, there is the thickening of the pituitary stalk (the diameter of the pituitary stalk exceeded 3.5 mm at the level of the median eminence of the hypothalamus) [Figure 1]a, loss of posterior pituitary bright spot on T1-weighted (T1w) images, and the presence of parasellar T2 dark sign [Figure 1]c. [2],[3] Parasellar extension can be seen as well [Figure 1]b and d. [2],[3] {Figure 1}

Parasellar T2 dark sign is specific for LYH. [4] All other features are sensitive but not specific for LYH and can be present in either case. Parasellar T2 dark sign suggests fibrosis and represents chronicity of disease. [4] Although parasellar T2 dark sign is specific for LYH, it is not present in all cases, hence its presence suggests diagnosis but its absence does not rule out the diagnosis of LYH. [4]

We had few cases of pituitary LYH that were proven clinically and on follow-up magnetic resonance imaging (MRI) scan showed the abovementioned features. One 39-year-old woman presented with amenorrhea, headache, vomiting, diplopia, and right eyelid ptosis. On MRI of the brain, there was thickening of the pituitary stalk with enlarged homogeneously enhancing pituitary gland and parasellar extension (right > left). Another 34-year-old female presented with amenorrhea and headache. MRI showed parasellar T1 and T2 hypointensity that was referred to as T2 dark sign. It suggests fibrosis due to long-standing inflammation.

These features on MRI are pointers to accurate diagnosis in appropriate clinical setting and could avoid unnecessary surgery.

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