CT 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.

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.

Presumed Pituitary Abscess Without Infectious Source Treated Successfully With Antibiotics Alone

A 12-year-old girl developed acute frontal headache and severe visual loss in both eyes. A presumptive diagnosis of pituitary abscess was made on the basis of suggestive magnetic resonance imaging findings. These consisted of a large non-enhancing area within the pituitary gland and thin irregular glandular rim enhancement. There was no evidence of pre-existing intracranial or systemic infection. The patient recovered completely after treatment with intravenous and oral antibiotics without surgical drainage. This case highlights the need for a high index of suspicion for pituitary abscess based on unusual imaging findings even when there is no source of infection.

Primary pituitary abscess: case report

Pituitary abscesses are potentially life-threatening lesions if not appropriately diagnosed and treated. The authors have operated on more than five hundred cases of pituitary tumors and only one represented a case of pituitary abscess. A 35-year-old woman was investigated for chronic frontal headache. CT scan showed a cystic sellar lesion with ring enhancement after contrast injection leading to an initial diagnosis of pituitary adenoma. She underwent a sublabial transsphenoidal approach to the pituitary gland. After dural opening, purulent material was obtained and no tumor or other associated lesion was detected. There was no evidence of current or previous septicemic illness, meningitis, cavernous sinus thrombosis or sinus infection. Cultures were negative. She was put on antibiotics and discharged after 4 weeks. Nowadays, 10 years after treatment, she is doing well, with no anterior pituitary hormone deficit. MRI shows a partially empty sella without residual lesion and the pituitary stalck is in the midline. The early diagnosis and adequate treatment of this life-threatening lesion may result in excellent prognosis.

Magnetic resonance imaging and computerized tomography images in a case of pituitary abscess

A 29-year-old male patient with clinical manifestations of panhypopituitarism and diabetes insipidus is presented. The clinical and laboratory evaluation of the pituitary reserve confirmed a total pituitary insufficiency. Computed tomography (CT) scan demonstrated a low-density lesion suggesting a pituitary tumor with suprasellar extension, and magnetic resonance imaging (MRI) revealed a pituitary mass with decreased signal intensity on T1-weighted images and capsular contrast enhancement after gadolinium injection. The surgical procedure was the treatment of choice. During surgery a large amount of purulent material was removed. With light microscopy, chronic non-specific inflammation and a pituitary abscess capsule were demonstrated in the tissue. The results of the cultures revealed coagulase negative staphylococcus. The post-operative course was uneventful and, as the patient was pituitary-deficient, he was on replacement therapy and was being followed-up. Pituitary abscess is an exceptional lesion in the literature and despite the advent of CT and MRI, its preoperative diagnosis still remains difficult. However, the presence of an intrasellar expansive process with liquid center and contrast enhanced outline should suggest the possibility of an abscess. Sellar round cystic mass isointense or hypointense to grey matter on T1, high intensity signal on T2, or opposite pattern with a peripheral rim enhancement following gadolinium injection, and diabetes insipidus may all be suggestive of a pituitary abscess.

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.

Intrasellar abscess following transsphenoidal surgery

BACKGROUND

Intrasellar abscess following transsphenoidal surgery has been described only twice in the English language medical literature. Overall mortality associated with intrasellar abscesses is 51%, while mortality in reported cases not treated surgically is 100%.

METHODS

Two cases of intrasellar abscess following uncomplicated transsphenoidal surgery for pituitary pathology are reported. The incidence, radiographic features, clinical presentations, and treatment of intrasellar abscesses are discussed.

RESULTS

Both patients described underwent uncomplicated transsphenoidal procedures for treatment of a primary pituitary lesion. Neither developed postoperative CSF rhinorrhea, and initial recovery was uneventful. The first patient presented with new symptoms several weeks after transsphenoidal surgery; the second patient almost two years postoperatively. The first displayed signs of an expanding sellar mass, requiring transsphenoidal drainage and postoperative antibiotics. The second presented with recurrent meningitis without discernible CSF leak, and was treated with transnasal endoscopic drainage in conjunction with antibiotic therapy.

CONCLUSIONS

The high mortality associated with intrasellar abscess mandates its inclusion in the differential diagnosis of patients presenting with symptoms of meningitis or an expanding sellar mass after transsphenoidal intervention. Although antibiotic therapy is an important adjunct, surgical drainage is required for definitive treatment.

Candidal pituitary abscess: case report

We report a case of a culture-proven intrasellar Candida albicans abscess. A 36-year-old woman presented with a history of headaches, menstrual irregularities, and mild symptoms of diabetes insipidus. She was neurologically intact at the time of a transsphenoidal surgery for a presumed pituitary adenoma. An extensive work-up revealed that although the patient was seronegative for human immunodeficiency virus, she was immunocompromised with a T-cell dysfunction. Fungal abscesses of the pituitary gland have rarely been reported. This is the first documented case of a patient who is seronegative for human immunodeficiency virus who becomes infected by an ordinarily innocuous fungus, Candida albicans.

Pituitary abscesses. Report of three cases

Three cases of pituitary abscess are presented. In spite of improvements in radiological evaluation, preoperative diagnosis of pituitary abscess is quite difficult and definite preoperative diagnosis is rare in the literature. In our three cases, diagnosis was made postoperatively. Pituitary abscesses are associated with high mortality and morbidity. When first suspected, prompt antibiotic therapy should be considered. Early operative drainage seems to be an important factor in decreasing this high mortality and morbidity.

Magnetic resonance characterization of a long-standing pituitary abscess

A 56-year-old male patient with panhypopituitarism is presented. Magnetic resonance (MR) examination of the pituitary region revealed a pituitary mass with markedly increased signal intensity on T1-weighted images and low signal intensity on T2-weighted images. At surgery, a large amount of purulent material was removed. At light microscopy, the tissue was demonstrated to be a pituitary abscess occurring in an otherwise normal pituitary gland. The high signal intensity on T1-weighted images does not correspond to the only MR description of a pituitary abscess given until now, reporting a mass isointense to white matter. These signal characteristics could emanate from the presence of small amounts of blood breakdown products in the proteinaceous content of the abscess. MR appearance of a pituitary abscess is possibly aspecific and could depend on the pathological composition of the lesion.

Primary pituitary abscess: surgical management and endocrine assessment in three cases

Three cases of pituitary abscess are described. All were women with varying degrees of anterior pituitary dysfunction, diabetes insipidus and headaches. None had visual disturbance. A history of prior head injury was obtained in both young women who developed secondary amenorrhoea and hyperprolactinaemia. All three had low density, thick rim intrasellar masses on computed tomography scanning. Certain aspects of the diagnosis and surgical management of this rare condition are discussed with particular emphasis on the importance of pre- and postoperative endocrine assessment and preoperative diagnosis and proper surgical management.