A case of craniopharyngioma presenting as rapidly progressive dementia.

Rapidly progressive dementia (RPD) is generally obvious to family member but often difficult for physicians to pinpoint the underlying pathology. Some common causes, such as prion's disease, Alzheimer's disease, central nervous system vasculitis, or infection, might present with disease-specific signs or symptoms where many etiologies do not produce such warning signs. Here, we are presenting a case who attended the psychiatric clinic for decreased motivation to do work, easy fatigability, infrequent falls, recent memory impairment, increased appetite, polydipsia and polyuria, and provisionally diagnosed with RPD. Magnetic resonance imaging revealed solid cystic lesion in suprasellar location involving hypothalamus, optic chiasma, and optic tracts, compressing the floor of the third ventricle suggestive of craniopharyngioma which is one of the very few reports in literature.

INTRODUCTION

Rapidly progressive dementias (RPDs) are neurological conditions that develop subacutely over weeks to months or acutely over days. In contrast to most dementing conditions that take years to progress, RPD can be quickly fatal. While evaluating the causes for RPD, we should rule out infectious, vascular, tumors, autoimmune, metabolic, and toxic causes.[1]

Here, we are presenting a case of RPD in which the cause came out to be craniopharyngioma.

CASE REPORT

Mr. X, a 51-year-old male, a graduation degree holder, with no psychiatric or serious medical illness in the past as well as in family, presented to us with an illness for 7-month duration. It was an insidious onset, continuous course with symptoms initially characterized by decreased motivation in workplace, easy fatigability for 7 months, and infrequent falls with giddiness for 6 months, recent memory impairment and increased appetite for 4 months, inability to walk steadily for 2 months, and bladder incontinence for 1 month with symptoms suggestive of polydipsia and polyuria. There was no history of swallowing or speech problems, abnormal eye movements, apraxia, agnosia, paraesthesia, chronic exposure to any toxin, recent infection or fever, substance abuse, hallucinatory behavior, excessive anxiety, or obsessive-compulsive symptoms.

On examination, he was observed to be little drowsy but attentive on continuous cues, not oriented to time and person. He was also noted to walk with a broad-based gait. Mini Mental State Examination (MMSE) done was 20/30 (impaired orientation, recall, and constructional ability). On cognitive examination, the attention was initiated but not sustained. Recent memory was impaired. He could not do complex mathematics, and abstraction was at semiabstract level. He had right plantar extensor, positive frontal release signs, and finger-nose incoordination.

A provisional impression of RPD was made based on the International Classification of Diseases-10 criteria. Magnetic resonance imaging (MRI) revealed well-defined lobulated T1-hypointense and T2-heterogenous hyperintense solid cystic lesion in suprasellar location measuring 4.7 cm × 4.7 cm × 3.1 cm. Intensely heterogeneously enhancing internal solid component with peripheral cystic component demonstrating thin, smooth peripheral rim enhancement. No diffusion restriction within the lesion with solid component demonstrating multiple foci of blooming on susceptibility-weighted images may represent calcifications. The lesion involves the hypothalamus, optic chiasma, and optic tracts, which are not visualized separately. Superiorly, the lesion compresses the floor of the third ventricle. The lesion reaches up to the interpeduncular cistern posteriorly with splaying of the cerebral peduncles. Inferiorly, the pituitary and infundibulum are visualized separately from the lesion. Linear T2 and Flair hyperintensity is seen along the right optic tract (Figure 1, describing pre surgery MRI findings). MR spectroscopy from the enhancing solid component reveals raised choline with choline/creatine ratio of 2–2.3 and small lipid lactate doublet. Other basic investigations, such as routine hematology, renal and liver function tests, thyroid function tests, chest X-ray, blood culture, urine routine, and microscopy, were within normal limit.

Figure 1

Magnetic resonance imaging before surgery

An immediate neurosurgery opinion was taken that opined regarding surgical procedure. Ophthalmology consultation was sought for any visual impairment; however, his field of vision and acuity were found to be normal. Ophthalmologist also suggested for immediate surgical intervention to prevent impending visual loss. After 3 days, the patient got operated-right pterional craniotomy and excision of craniopharyngioma under general anaesthesia (GA) (Figure 2, describing post surgery MRI findings). After one month of surgery, detailed evaluation of pituitary hormones was also done which was found to be normal. Over 2 months, the patient showed a significant improvement in memory with most recent MMSE of 30/30. The patient did not have impairment in orientation, recall, constructional, and mathematical ability. On proverb test, he could answer to the abstract level. After 4 months, he started working and was doing well till date.

Figure 2

Magnetic resonance imaging after surgery

DISCUSSION

RPD is easily recognized by family members because of its dramatic departure from baseline functioning; however, management is the toughest challenge. In 95.4% scenarios, there will be a definitive diagnosis, the most common being spongiform encephalopathy attributed to Creutzfeldt–Jakob disease (CJD) (58.5%) second most is the neurodegenerative diseases such as Alzheimer's disease (22.5%). About 18.8% of cases are potentially treatable; hence, early diagnosis is very important.[2] Often, the challenge is differentiating reversible cause from CJD. Furthermore, it is seen that clinicopathological diagnostic agreement is present in 94% of prion RPD but only in 21% of nonprion RPD which makes the later difficult to diagnose.[3] Sensorimotor impairment, cognitive decline, and behavioral sequel, such as personality change, hallucinatory behavior, and rapid worsening of functioning, are common warning signs of RPD but often do not present during the onset.[1] Noninvasive investigations such as computed tomography (CT) scan or MRI followed by invasive techniques such as brain biopsy is used to diagnose the pathology behind RPD.[2] Symptoms, such as impaired memory, apathy, abnormal speech and gait, headache, seizure, or myoclonus, often represent the findings of brain tumor in CT scan or MRI. Among brain tumor, primary central nervous system lymphoma and paraneoplastic tumor are the common diagnoses of RPD.[4] Craniopharyngioma as a specific cause of RPD is rarely mentioned in literature. Craniopharyngioma, remnants of the embryonic Rathke's pouch, is among the most frequently reported tumors that can manifest in both childhood (most common) and adulthood, usually involving the posterior hypothalamus. As most are suprasellar, the patients usually present with visual abnormalities and headaches. In adulthood, slow-growing tumors result in dementia syndrome, endocrine dysfunction, and food intake dysregulation. More rapid processes present with disturbances of consciousness, temperature, and autonomic dysregulation. Furthermore, hypogonadism, hyperprolactinemia, diabetes insipidus, and weight gain are common. Furthermore, there is cognitive deterioration and personality change without evidence of psychosis.[5] Bartlett Jr reported case series of 85 patients in 1971, among them 32% developed dementia at an earlier age such as 45 years old,[6] later a case was reported in an elderly with presenting symptoms of dementia.[7] There is only a handful of literature in this regard. In our case, the patient had significant cognitive dysfunction with rapid deterioration. He had repeated falls which could be explained due to hypothalamus involvement leading to autonomic dysfunction.[8] Furthermore, repeated falls without medullar involvement suggest frontal lobe dysfunction. Moreover, the frontal lobe dysfunction can reduce motor automaticity which necessitates an individual to have greater conscious control during automated task such as walking. Hence, one can sustain repeated falls.[910] As the patient had impaired abstractibility and poor attention, the frontal lobar dysfunction could be presumed even though MRI findings in this regard were not profound.[10] The patient had the involvement of the third ventricle and lateral hypothalamus which could explain the symptoms of polydipsia and polyuria.[11] Preoptic area through the lateral hypothalamus into the ventral midbrain is the area related to motivation which was affected in our patient.[12] Hence, these were the clinical pearls of the diagnosing the tumor before neuroimaging.

Hence, the structural method should be implemented while handling a case of RPD as delay in diagnosis may further worsen a reversible condition.[1] In our case, we could diagnose him in few days and approach for earliest management. The patient was found to be gradually improving after surgery which again proved the causation of the RPD.

Hence, we need to be vigilant while dealing with RPDs, and a detailed assessment is needed immediately without a delay so that rapid treatment of the underlying cause can be done.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.