Abscess formation within a Rathke's cleft cyst

Secondary hypophysitis associated with Rathke's cleft cyst resembling a pituitary abscess

Background

Although rare, cases of hypophysitis resembling a pituitary abscess (PA) have been reported. Differential diagnosis between hypophysitis and PA is crucial as the two diseases require different treatments.

Case Description

A 38-year-old woman with headaches underwent head magnetic resonance imaging (MRI), which revealed an 11-mm mass lesion in the sella turcica. Due to breastfeeding, contrast-enhanced MRI was avoided. Pituitary adenomas and Rathke's cleft cyst (RCC) were suspected, and she was initially treated conservatively. Five months later, she acquired syndrome coronavirus two infections, and while the fever subsided with acetaminophen, the headache persisted. One month later, the headache worsened, followed by fever and diabetes insipidus. MRI revealed a pituitary cystic mass with ring-shaped contrast enhancement on T1-weighted MRI and increased signal intensity on diffusion-weighted imaging (DWI). PA was suspected, and emergency endoscopic transsphenoidal surgery was performed. The microbiological examination of the yellowish-brown content drained from the cystic mass was negative. Microscopically, the cystic lesion was covered with ciliated columnar epithelium and stratified squamous epithelium, with a dense inflammatory cell infiltrate consisting mainly of lymphocytes and plasma cells observed around the cyst. This supported the diagnosis of secondary hypophysitis associated with RCC without PA.

Conclusion

We report a case of hypophysitis secondary to RCC resembling PA with ring-shaped contrast enhancement on MRI and increased signal intensity on DWI. This case emphasizes the need for cautious diagnosis of secondary hypophysitis due to RCC in individuals with MRIs and clinical manifestations resembling an 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.

Rathke's Cleft Cyst Abscess with a Very Unusual Course

Infected Rathke's cleft cysts (RCC) are extremely rare with only a few published cases. We report the case of a 31-year-old man who presented with headaches, visual disturbance, and hypopituitarism secondary to an infected RCC with extension of abscesses along the optic tract. Magnetic resonance imaging showed ring enhancing cystic lesions within an expanded sella with suprasellar and intraparenchymal extension. The radiological appearance suggested a high-grade optic glioma, but an endoscopic transsphenoidal biopsy revealed frank pus in the pituitary fossa, which subsequently grew Staphylococcus aureus . Pathological examination of the cyst wall showed an inflamed RCC. Following a prolonged course of intravenous antibiotics, the infection resolved and vision improved. RCC abscesses are rare and the intracranial extension of the infection in our case makes it unique.

Rathke's cleft cyst infections and pituitary abscesses: case series and review of the literature

PURPOSE

Pituitary abscesses (PAs) are a rare clinical entity which may arise from normal pituitary tissue or underlying lesions within the gland. Rathke's cleft cysts (RCCs) are not commonly associated with the development of PA.

METHODS

Retrospective chart review of three patients with PAs within RCCs at a single university center and review of the literature.

RESULTS

Three cases are reported. The first case presented with fever and headache and a history of prior surgery due to RCC and a recent respiratory tract infection. The second case had a history of recent skin infections and presented with sudden onset headache and hypopituitarism. In the third case, chronic visual field impairment prompted an ophthalmologic evaluation resulting in a diagnosis of an adenoma and an infected RCC. In all three cases, an endoscopic endonasal approach was performed to drain infected tissue and allowed microbiological identification of gram-positive cocci, followed by treatment with antibiotics for at least three weeks. Cases in the literature are scarce and the diagnosis is usually made intraoperatively due to non-specific manifestations and imaging. PAs arising from underlying pituitary lesions are less common than primary PAs. Differential diagnosis should include pituitary apoplexy, hypophysitis and other cystic lesions.

CONCLUSION

PAs occurring in RCCs are infrequent. Clinical manifestations are commonly subacute, without septic symptoms. Imaging is usually non-specific. Preoperative diagnosis is infrequent and a broad differential diagnosis should be considered. Empirical antimicrobial therapy should be initiated and adjusted after obtaining cultures to reduce the rate of recurrence and improve clinical outcomes.

Secondary pituitary abscess following transsphenoidal surgery with recurrent meningitis: A case report

RATIONALE

The transsphenoidal surgical (TS) approach to sellar masses is the preferred surgical route in most cases. Secondary pituitary abscess (PA) following TS is an extremely rare but serious postoperative complication with potentially high disability and mortality.

PATIENT CONCERNS

We describe an uncommon case of secondary PA in a 42-year-old woman, who underwent uncomplicated transsphenoidal procedures without cerebrospinal fluid leak, to treat primary Rathke cleft cyst. Without obvious cause, the patient suffered recurrent meningitis with complaints of headache, hyperpyrexia, and chills from 1 month after the operation.

DIAGNOSIS

There were no significant imaging findings until a new rim-enhancement lesion was seen in the sellar region on magnetic resonance imaging during the 6th episode of meningitis 11 months after the initial surgery. A diagnosis of secondary PA was considered; INTERVENTIONS:: Therefore, she underwent a 2nd TS with pus evacuation and antibiotic treatment.

OUTCOMES

She improved remarkably and had no recurrence of symptoms during the 9-month follow-up.

LESSONS

Our aim was to present this rare case and discuss the most likely etiologies and preventive measures for this condition. In patients with recurrent meningitis but dormant imaging manifestations after TS, the possibility of secondary PA should considered. Adequate surgical drainage with microbiology-guided antibiotic therapy is the 1st choice for treatment.

Rathke cleft cyst masquerading as pituitary abscess: A case report

BACKGROUND

Rathke cleft cyst (RCC) is a rare cystic sellar entity, which is usually small in size and asymptomatic in most patients. RCC presenting panhypopituitarism and a cystic lesion with rim enhancement on magnetic resonance imaging is extremely rare. Therefore, it is easy to be misdiagnosed as pituitary abscess because of the similar clinical manifestations and neuroimaging changes.

CASE SUMMARY

We report a rare case of RCC masquerading as pituitary abscess clinically and radiologically with no evidence of central nervous system infection. The patient was initially suspected to be diagnosed with pituitary abscess, which was denied by the histopathological findings of RCC with no intraoperative drainage of abscess.We present an uncommon case of RCC masquerading as pituitary abscess in a 62-year-old Chinese male patient. The patient was admitted to Peking Union Medical College Hospital complaining of severe frontal pulsatile headache, visual acuity deficit, polyuria, polydipsia, and slight disturbance of consciousness. The biochemical and endocrinological examinations revealed severe hyponatremia and panhypopituitarism. Magnetic resonance imaging showed a sellar lesion with the apparent cystic change and rim enhancement. Accordingly, pituitary abscess was misdiagnosed at the beginning.The patient received hormone replacement therapy and underwent a trans-sphenoidal surgery. The surgical findings were uneventful. The histopathological examinations showed no infiltration of inflammatory cells or pus, and proved the lesion to be RCC.

CONCLUSION

Through this rare case, we aim to emphasize that the differential diagnosis of sellar lesions requires constant vigilance and that RCC may lead to clinical and radiological changes similar with pituitary abscess.