Prolonged postoperative pyrexia (PPP) due to Mollaret’s meningitis following endoscopic transsphenoidal surgery (eTSS) for an intracranial epidermoid cyst can be confused with postoperative meningeal infection after transsphenoidal resection, especially in the middle of the COVID-19 pandemic. Anosmia, as well as dysgeusia, cannot be evaluated in patients of eTSS for a while after surgery. We report a case of an infundibular epidermoid cyst with post-eTSS Mollaret’s meningitis (MM). The post-eTSS MM caused vasopressin-analogue-resistant polyuria (VARP) in synchronization with PPP. A 59-year-old man experiencing recurrent headaches and irregular bitemporal hemianopsia over three months was diagnosed with a suprasellar tumor. The suprasellar tumor was an infundibular cyst from the infundibular recess to the posterior lobe of the pituitary, which was gross-totally resected including the neurohypophysis via an extended eTSS. Since awakening from general anesthesia after the gross total resection (GTR) of the tumor, the patient continuously had suffered from headache until the 13th postoperative day (POD13). The patient took analgesics once a day before the surgery and three times a day after the surgery until POD11. Pyrexia (37.5–39.5 degree Celsius) in synchronization with nonnephrogenic VARP remitted on POD18. Intravenous antibiotics had little effect on changes of pyrexia. Serum procalcitonin values (reference range <0.5 ng/mL) are 0.07 ng/mL on POD12 and 0.06 ng/mL on POD18. His polyuria came to react with sublingual desmopressin after alleviation of pyrexia. He left the hospital under hormone replacement therapy without newly added neurological sequelae other than hypopituitarism. After GTR of an infundibular epidermoid cyst, based on values of serum procalcitonin, post-eTSS MM can be distinguished from infection and can be treated with symptomatic treatments. The postoperative transient nonnephrogenic VARP that differs from usual central diabetes insipidus can react with sublingual desmopressin after alleviation of PPP in the clinical course of post-eTSS MM. An infundibular epidermoid cyst should be sufficiently resected in one sitting to minimize comorbidities, its recurrence, or postoperative MM to the utmost.
Mollaret’s meningitis, a benign recurrent aseptic disease, is known to be associated with intracranial and intraspinal epidermoid cysts [
A 59-year-old man presented with a three-month history of gradually progressive blurred vision with headaches (mainly retrobulbar pain). The headaches were frequently associated with coughs or sneezes. Magnetic resonance (MR) imaging demonstrated a sellar-suprasellar tumor compressing the optic chiasm superiorly (Figures
Precontrast T1-weighted axial image showing a suprasellar tumor compressing the optic pathway (a). Gadolinium-enhanced axial image showing an enhanced rim of the tumor (b). The contents of the tumor are of low signal intensity on the T1-weighted image (a) and Gadolinium-enhanced image (b), slightly high on T2-weighted image (c), iso on fluid-attenuated inversion recovery image (d), and relatively high on diffusion-weighted image (e) and T2∗-weighted image (f). Contrast-enhanced computed tomography showing a cystic lesion (g) from the sella turcia to the suprasellar space (h). Calcified components are not found in it. Postcontrast magnetic resonance imaging shows the enhanced cystic wall displacing the optic chiasm upward (i). This cystic lesion occupies the suprasellar region but not the third ventricle (h), (j). Goldmann perimeter reveals irregular bitemporal hemianopsia (k). Constriction of the visual field is more predominant in the right eye than in the left eye (k).
Under general anesthesia, an endoscopic transsphenoidal surgery was performed. The sellar floor and the adjacent tuberculum sellae were removed to expose the dura around the sella turcica. The dura was opened (Figure
The intercavernous sinus has been cut after cauterization (a). A Y-shaped dural incision is made (a). The cyst wall is found above the pituitary gland (b). Vascular streaks are found on the cyst wall, indicating the pituitary stalk is tumorized (b). The cyst is displacing the optic chiasm (c). The cyst contents are aspirated via a long needle (d). After the aspiration (d), the cyst is shrunken so that the working space in this tumor resection is secured. An indentation is observed in the inferior surface of the decompressed optic chiasm (e). The solid cyst contents appeared as tissue debris, keratin, solid cholesterol, and their mixtures, which were meticulously removed (f). Since the cyst wall is the tumorized pituitary stalk, the cyst was gross-totally removed from the intrasellar part to the infundibular part (g). The opened skull base (h) is reconstructed with a fat-on-fascia graft plug [
Histopathological examination shows features of the dermoid cyst. The lining is typically a squamous epithelium adjacent to glial tissues with inflammation (a). The cyst lumen contains keratin (b). CW: cyst wall and K: keratin.
The displaced optic chiasm (a, b, c, and d) is successfully decompressed, and the cyst is totally resected (e, f, g, and h) on MR imaging at 4 months (19 weeks) weeks after surgery.
Only six cases of infundibular epidermoid cysts were reported prior to this report (Table
Characteristics of previous and current case reports of pituitary stalk epidermoid cysts.
Paper | Age/sex | Presentation | Imaging characteristics | Operative approach | Postoperative status |
---|---|---|---|---|---|
Costa et al., 2013 [ | 27-year-old female | Amenorrhea, galactorrhea, polyuria, and polydipsia | Mixed signal, bilobed rim and enhancing cystic lesion | Endoscopic endonasal extended transsphenoidal | Not reported |
Nakassa et al., 2017 [ | 54-year-old female | Headache, visual disturbance, polyuria, and polydipsia | Mixed signal and nonenhancing cystic lesion | Endoscopic endonasal | Persistent DI and subjective visual fields improvement |
McCormack et al., 2018 [ | 36-year-old female | Headache and visual disturbance | Multilocular T1 hypointense, T2 hyperintense, and rim-enhancing lesion | Endoscopic endonasal extended transsphenoidal | Transient DI |
Montaser et al., 2018 [ | 49-year-old female | Headache | Mixed signal and nonenhancing sellar/suprasellar cyst extending into the third ventricle | Endoscopic endonasal extended transsphenoidal | Persistent DI |
Khan et al., 2019 [ | 55-year-old male | Decreased visual acuity | Mixed signal and rim-enhancing cystic lesion | Endoscopic endonasal extended transsphenoidal | Panhypopituitarism and subjective visual fields improvement |
Lee et al., 2020 [ | 63-year-old male | Polydipsia and polyuria | T2 hyperintense and rim-enhancing cystic lesion | Pretemporal craniotomy | Persistent DI |
Current case | 59-year-old male | Headache and visual disturbance | Rim-enhancing cystic lesion | Endoscopic endonasal extended transsphenoidal | Panhypopituitarism, persistent DI, and visual fields improvement |
From this case, we have found two things that the previous reports did not refer to [
The PPP should be distinguished from a symptom of postoperative bacterial meningitis. Because healthcare-associated meningitis or ventriculitis is a serious complication in different neurosurgical procedures and is associated with significant morbidity and mortality [
Fever is a relatively common occurrence among patients in the intensive care setting. Although the most obvious and concerning etiology is sepsis, drug reactions, venous thromboembolism, and postsurgical fevers are all on the differential diagnosis [
Serum procalcitonin levels seem to be the best marker in differentiating between bacterial and viral meningitis in adults [
The postoperative hard-to-control polyuria: pitressin/desmopressin-resistant polyuria, which should instead be called vasopressin-analogue-resistant polyuria (VARP), differs from usual central diabetes insipidus (DI). VARP came to react with sublingual desmopressin after alleviation of pyrexia in the clinical course of post-eTSS Mollaret’s meningitis in our case. The postoperative VARP is something different from usual DI: hypernatremia associating polyuria was not observed, indicating excessive excreted urinary natrium quantity during VARP. The VARP interacts with central hyperthermia (PPP), which suggests an involvement of the abovementioned hypothalamic dysfunction during the transient VARP. This VARP may belong to the category of cerebral salt wasting syndrome coexisting with DI [
PPP in this case was linked with the patient intake of NSAIDs. The VARP settled as the PPP remitted. Based on these findings and the clinical course, transient hypothalamic dysfunction (HD) is probably inflammation-induced. If so, NSAIDs and corticosteroids might be effective for HD after resection of infundibular epidermoid cysts.
This case is the first report of transient nonnephrogenic VARP synchronizing with PPP during Mollaret’s meningitis after resection of an infundibular epidermoid cyst. As a similar mechanism, Rathke’s cleft cysts (RCCs) sometimes present with acute onset, and the presentation is consistent with the features of pituitary apoplexy caused by pituitary adenoma [
In our case, even under GTR of an infundibular epidermoid cyst, a post-eTSS Mollaret’s meningitis continued until POD18 and had settled after POD19. If the eTSS resulted in insufficient resection, the Mollaret’s meningitis would not have settled and been long lasting. Thus, surgical gross total resection remains the mainstay for treatment of intracranial epidermoid cysts [
In the middle of the COVID-19 pandemic, prolonged pyrexia should be appropriately diagnosed and distinguished from coronavirus infection or other diseases. Physicians need to correctly approach this new disease in daily clinical practice, often representing a challenge in terms of differential diagnosis [
After GTR of the infundibular epidermoid cyst, based on values of serum procalcitonin, post-eTSS Mollaret’s meningitis can be distinguished from infection and can be treated with symptomatic treatments despite PPP. The postoperative VARP differs from usual central DI and can react with sublingual desmopressin after alleviation of PPP in the clinical course of post-eTSS Mollaret’s meningitis. An infundibular epidermoid cyst should be sufficiently resected in one sitting on the basis of its recurrence rate.
No data were used to support this study.
Informed consent was obtained from the patient.
There are no conflicts of interest to declare.
The authors would like to thank all laboratory medical technologists in Uonuma Kikan Hospital.