Case report: MRI and CT in a case of pituitary abscess

Pituitary abscess: a case report and systematic review of 488 cases

BACKGROUND

Pituitary abscess (PA) is a rare condition and not well understood. We aimed to describe a case and perform a comprehensive systematic review to explore presenting symptoms, radiological findings, endocrine abnormalities and mortality.

AIM

To identify presenting symptoms, radiological findings, endocrinological abnormalities and predictors of mortality for PA.

METHODS

We systematically reviewed the literature to identify all case reports of PA. Data regarding presentation, mortality, radiological findings, endocrinological abnormalities and treatment was extracted.

RESULTS

We identified 488 patients from 218 articles meeting the inclusion criteria. Mortality was 5.1%, with days to presentation (OR 1.0005, 95% CI 1.0001-1.0008, p < 0.01) being the only identified independent predictor of mortality. Mortality rates have decreased over time, with cases published prior to 2000 having higher mortality rates (OR 6.92, 95% CI 2.80-17.90, p < 0.001). The most common symptom was headache (76.2%), followed by visual field defects (47.3%). Classical signs of infection were only present in 43%. The most common imaging feature on magnetic resonance imaging (MRI) was high T2 and low T1 signal of the pituitary gland with peripheral contrast enhancement. Over half (54.8%) were culture negative, with the most common bacterial organism being staphylococcus aureus (7.8%) and fungal organism being aspergillus (8.8%). The most common endocrine abnormality was hypopituitarism (41.1%), followed by diabetes insipidus (24.8%). Whilst symptoms resolved in most patients, persistent endocrine abnormalities were present in over half of patients (61.0%).

CONCLUSION

PA is associated with significant mortality, with delayed presentation increasing risk of mortality. Ongoing endocrinological abnormalities are common. Given the non-specific clinical presentation, the appearance of high T2, low T1 and peripheral contrast enhancement of the pituitary on MRI should prompt consideration of this rare disease.

Secondary abscess arising in a craniopharyngioma

An abscess arising in a craniopharyngioma is rare, but has potentially high mortality and morbidity. Diagnosis is difficult because clinical and neuroradiological characteristics are not clearly defined. We report a patient with a pituitary abscess concomitant with a craniopharyngioma and discuss the pathophysiological mechanism. We discuss the previous five reports and suggest that abscesses with craniopharyngioma remain challenging clinical entities. We speculate that inflammation is a response to components of the ruptured epithelium of the cyst, thereby providing an explanation of the mechanism of abscess formation.

Rare sellar lesions

Sellar masses are associated most commonly with pituitary adenomas. Many other neoplastic, inflammatory, infectious, and vascular lesions, however, may affect the sellar region and mimic pituitary tumors. These lesions must be considered in a differential diagnosis. This article describes the characteristics of rare sellar masses that provide clues to their differential diagnosis.

Successful treatment of pituitary abscess with oral administration of sparfloxacin

Pituitary abscess is a rare infection and it is difficult to make the correct diagnosis. It is usually treated by a combination of surgical drainage and intravenous administration of antibiotics. We describe a 74-year-old woman with recurrent meningo-encephalitis due to pituitary abscess. The abscess increased in size in spite of the intravenous administration of panipenem/betamipron (PAPM/BP), clindamycin (CLDM) and chloramphenicol (CP). Finally she was successfully treated with oral administration of sparfloxacin (SPFX) without operation.

Pituitary abscess

Pituitary abscess is a rare disease, but one with potentially high mortality and morbidity. We present a 46-year-old man with progressive visual disturbance and general malaise for 1 year. Endocrine studies revealed hypopituitarism, and magnetic resonance imaging revealed a pituitary lesion with suprasellar extension. We attempted to excise the lesion using a transsphenoidal approach, but pus in the pituitary fossa was found at operation, and no tumour was identified. The culture yielded coagulase-negative Staphylococcus. Antibiotics were administered for 3 weeks, and the patient made a good postoperative recovery. He required life-long hormone replacement therapy. After one and a half years of follow-up, he was well and had no evidence of focal or systemic infection. We review the literature regarding pituitary abscess and discuss the appropriate treatment and possible pathological mechanism.

Blurred Vision Caused by Inflammation of the Optic Nerves Due to a Pituitary Abscess-Case Report-

A 48-year-old woman was admitted to our institution complaining of headache and a 2-month history of blurred vision and increased urinary volume. T(1)-weighted magnetic resonance (MR) imaging with gadolinium showed a ring-enhanced mass lesion in the pituitary. Fluid-attenuated inversion recovery MR imaging showed high-intensity lesions in the optic nerves, hypothalamus, and thalamus. The histological diagnosis was pituitary abscess. The blurred vision was caused by inflammation, but not compression, of the optic nerves due to the pituitary abscess outside the hypophysis.

A case of anterior hypopituitarism showing recurrent pituitary mass associated with central diabetes insipidus

We report a case of anterior hypopituitarism showing recurrent pituitary mass associated with central diabetes insipidus. A 76-year old woman was hospitalized with general fatigue and 5 kg body weight loss. Endocrinological examinations and pituitary provocative tests demonstrated hypopituitarism and central diabetes insipidus. T1-weighted image of magnetic resonance imaging (MRI) revealed an intrasellar cystic mass with ring enhancement suggesting pituitary abscess. MRI films subsequently obtained from another hospital and studied retrospectively showed intrasellar cystic mass with ring enhancement 4 years earlier, and a mass shape that was decreased after 2 years. Over the subsequent years, the patient has remained asymptomatic with hormone replacement therapy only. Cystic pituitary adenoma or Rathke's cleft cyst with repeated infection may be involved in the repeated change of pituitary mass shape although neither pituitary surgery nor a pituitary biopsy was performed because of the patient's age and condition. It is reported that apparent recurrence of Rathke's cleft cysts after initially successful surgery was higher than suggested by previous reports, and that long-term follow-up with pituitary imaging and neuroophthalmological assessment is essential. Careful evaluation by follow-up brain MRI is needed in the present case to prevent future recurrence of pituitary abscess.

Pituitary abscess showing high uptake of thallium-201 on single photon emission computed tomography--case report

A 32-year-old female presented with a rare case of pituitary abscess manifesting as homonymous hemianopsia. Serum prolactin level was slightly high (40.8 ng/ml). Magnetic resonance (MR) imaging showed the content of the lesion as homogeneously isointense on the T1-weighted images and hyperintense on the T2-weighted images. The capsule of the lesion, which appeared thin and smooth, was enhanced by gadolinium. Dural enhancement around the sella turcica was also recognized. Thallium-201 single photon emission computed tomography (201Tl SPECT) showed homogeneous high accumulation in the pituitary region on both the early and delayed images. The lesion was treated via a transnasaltranssphenoidal approach. The cystic lesion contained pus and the capsule consisted of normal pituitary gland with inflammatory changes. The patient was treated with antibiotics for 3 weeks and the pituitary abscess was cured completely. Pituitary abscess can be differentiated from pituitary adenoma as lesion with a homogeneous high uptake on 201Tl SPECT on both the early and delayed images, and no enhancement of the central portion on MR images.

Bacterial Pituitary Abscess: an Unusual Cause of Panhypopituitarism

OBJECTIVE

To describe a case of primary bacterial pituitary abscess manifesting as hypopituitarism.

METHODS

We present the case history, hormonal and bacteriologic data, and findings on imaging studies in a 34-year-old man.

RESULTS

The patient had an 8-month history of intermittent fever, headache, nausea, vomiting, and weight loss. Because a computed tomographic scan of the head showed a cystic sellar mass with ring enhancement, he was referred to our medical center. On physical examination, he showed signs of meningeal irritation and had mild hypotension. Hormonal evaluation revealed evidence of hypocortisolism, hypothyroidism, and hypogonadism. Three weeks after treatment with antibiotics and hormonal replacement, he underwent transsphenoidal surgical exploration and evacuation of purulent material from the sella. On culture, this specimen grew coagulase-negative staphylococci and Propionibacterium granulosum. Nine months later, dynamic testing showed persistent central hypocortisolism, hypothyroidism, and hypogonadism.

CONCLUSION

Bacterial pituitary abscess is rare but manifests similar to other pituitary masses with headaches, visual field defects, and hormonal disturbances. For the correct preoperative diagnosis of this condition, the physician must have a high index of suspicion, and the characteristic ring enhancement must be present on imaging studies.

Diagnosis and management of pituitary abscess: a review of twenty-four cases

OBJECT

Pituitary abscess is a rare but serious intrasellar infection. To better determine the salient signs and symptoms that help in making the diagnosis, and to determine the most appropriate treatment, the authors reviewed their experience in a series of 24 patients treated at the University of California at San Francisco.

METHODS

Nine of the patients were female and 15 were male, and their mean age was 41.2 years (range 12-71 years). Surprisingly, most patients in our series presented with complaints and physical findings consistent with a pituitary mass, but rarely with evidence of a serious infection. Headache, endocrine abnormalities, and visual changes were the most common clinical indicators; fever, peripheral leukocytosis, and meningismus were present in 33% or fewer of the patients. Imaging tests demonstrated a pituitary mass in all patients, but the features evident on computerized tomography and magnetic resonance studies did not distinguish pituitary abscesses from other, more common intrasellar lesions. Because of the ambiguous clinical features and imaging findings, most abscesses were not diagnosed before treatment; rather, the diagnosis was made during surgical exploration of the sella turcica, when the surgeon encountered a cystic mass containing pus. There were only two deaths in this series (8.3%). Patients presenting with headache and visual changes noted improvement in almost all cases; patients with endocrine dysfunction generally did not recover normal pituitary function, but were easily treated with hormone replacement therapy.

CONCLUSIONS

Antibiotic therapy is suggested for patients who have symptoms of sepsis, or for patients in whom specific organisms are identified from cultures obtained during surgery. The transsphenoidal approach is recommended over open craniotomy for surgical drainage.