We present the case of a 43-year-old female presenting with secondary amenorrhea. Ten months prior to her admission, she presented with cessation of menses. Two months prior to admission, she had bilateral temporal loss of vision. The patient had no known prior infection or surgical procedure done. The patient was fertile and was able to conceive twice before. Apart from bitemporal hemianopsia, the rest of the physical examination was normal. Preoperative diagnosis was a non-functioning pituitary adenoma with hypopituitarism and optic chiasmal compression. During transsphenoidal surgery, instead of a solid mass, there was egress of purulent fluid upon puncturing of the capsule, findings compatible with an abscess. There was immediate improvement in visual acuity and visual fields after surgery. The patient was treated with intravenous ceftriaxone 2 g every 12 hours for 14 days. She developed a cerebrospinal fluid leak, which was successfully treated with acetazolamide and drainage of CSF via lumbar tap. There was no post-operative diabetes insipidus.
Magnetic resonance imaging (MRI) of the pituitary gland showed a hetergenous sellar-supra-sellar rim-enhancing mass (Figure 1).
Prior to surgery, her pituitary function was evaluated. Hyperprolactenemia as the cause of amenorrhea was ruled out because the prolactin level was normal at 92.2 uIU/ml, (N: 92-868). The patient had hypogonadotrophic hypogonadism as shown by the low follicle stimulating hormone (FSH) 0.35 miU/ml (N: 0.6-9.5) and low estradiol 29.7 pg/ml, (N 127-476). The patient also had secondary hypothyroidism her TSH 0.5 muiU/ml (N: 0.3-5.4) and fT4 9.4 pmol/L (N: 11-24) were both low. The patient also had secondary hypocortisolism with an 8AM cortisol of 39.54 nmol/L (N: 138-690). Serum adrenocorticotrophic hormone level was not determined.
The patient did not present with diabetes insipidus. The pre-operative serum sodium was 136 mmol/L, postoperative serum sodium was 135 mmol/L (N: 136- 144). Preoperative urine specific gravity was 1.024 and post operative urine specific gravity was 1.012.
There was no history of antecedent infection. There were no signs and symptoms such as fever. The patient had clear breath sounds and normal examination of the abdomen and genital area. Complete blood count showed a hemoglobin of 127 g/L, (N: 135-180), white blood cells 5.23 x109/L (N: 4.5-11.0), neutrophils 41% (N: 50-70%) and lymphocytes 46% (N: 20-50%).
Histopathology showed benign cyst contents (Figure 2). Gram stain of the abscess showed a PMN 0-1/OIF, Grampositive cocci 0-1/OIF. However, the abscess culture had no growth after 5 days of incubations. Work up for tuberculosis was also negative. Acid-fast bacilli smear was negative, as well as the polymerase chain reaction for M. tuberculosis.
The primary treatment for pituitary abscess is drainage. Empiric antibiotic coverage with Ceftriaxone 2 grams was given intravenously every 12 hours for 14 days. Patient had immediate improvement of blurring of vision post-operatively. The patient was able to count fingers during visual field confrontation test. There was no post-operative diabetes insipidus. Patient had cerebrospinal leak, which was resolved by giving acetazolamide. Patient was discharged on prednisone 7.5 mg/day and levothyroxine 100 mcg/tab, once a day.