What is the appropriate management for a patient with chronic diarrhea and epilepsy, presenting with hyperdensity in the bilateral occipital region on computed tomography (CT) scan?

Celiac Disease with Occipital Calcifications and Epilepsy

This clinical triad of chronic diarrhea, epilepsy, and bilateral occipital hyperdensity on CT is pathognomonic for celiac disease-associated occipital calcification syndrome, requiring immediate intestinal biopsy for diagnosis and initiation of a gluten-free diet alongside antiepileptic therapy. 1

Diagnostic Confirmation

Obtain intestinal biopsy immediately to confirm celiac disease, as this is found in 50% (8 of 16) of patients presenting with bilateral occipital calcifications (BOC) and epilepsy 1. The chronic diarrhea represents the gastrointestinal manifestation of celiac disease in this syndrome 2.

Neuroimaging Characteristics

• CT demonstrates flocculo-nodular, cortico-subcortical bilateral occipital calcifications without contrast enhancement and without lobar or hemispheric atrophy 1
• MRI is characteristically normal in this syndrome, which distinguishes it from other conditions 1
• The hyperdensity on CT represents calcification, not acute pathology requiring emergency intervention 1

Key Distinguishing Features

This syndrome differs from Sturge-Weber syndrome based on:

• Distribution pattern of calcifications (bilateral occipital vs. gyriform) 1
• Normal neurological examination 1
• Association with celiac disease rather than port-wine stain 1

Epilepsy Management

Seizure Characterization

Most patients (95%) with BOC develop epilepsy, typically manifesting as occipital partial epilepsy with relatively benign outcome 1. However, 20% may develop severe, drug-resistant epilepsy with frequent generalized and partial seizures leading to mental deterioration 1.

Initial Antiepileptic Treatment

• Start appropriate antiepileptic drugs based on seizure type 2
• For focal seizures originating from temporal regions (which can occur with autonomic symptoms including diarrhea), carbamazepine has demonstrated marked improvement 3
• MRI with epilepsy protocol is the preferred imaging modality for ongoing seizure evaluation, despite being normal in BOC syndrome 2

Monitoring and Prognosis

• Neurological examination remains normal in typical cases 1
• Monitor for progression to severe epilepsy with frequent, drug-resistant seizures 1
• The relationship between celiac disease and occipital calcifications requires ongoing investigation, but treatment of celiac disease is essential 1

Primary Treatment: Gluten-Free Diet

Institute strict gluten-free diet immediately upon confirmation of celiac disease 2, 1. This addresses the underlying pathophysiology and may influence both gastrointestinal and neurological manifestations.

Chronic Diarrhea Management

While awaiting biopsy results and dietary intervention:

• Evaluate for metabolic abnormalities, dehydration, and electrolyte disturbances 2
• Obtain stool studies if infectious etiology suspected (blood, fecal leukocytes, C. difficile, bacterial pathogens) 2
• Assess for alarm features: weight loss, nocturnal symptoms, blood in stool 2

Surgical Considerations

Surgery is NOT indicated for this syndrome, as:

• The calcifications are not resectable lesions 1
• Most patients respond to medical management of epilepsy 1
• The underlying pathology is metabolic/immunologic (celiac disease) rather than structural 1

Surgical evaluation would only be appropriate if:

• Epilepsy becomes medically refractory after 2 years of appropriate antiepileptic therapy 4, 5
• Additional epileptogenic foci are identified on functional imaging (FDG-PET, ictal SPECT) 2

Critical Pitfalls to Avoid

• Do not mistake this for posterior reversible encephalopathy syndrome (PRES), which shows bilateral hyperintensities on FLAIR MRI (not calcifications on CT) and typically resolves 6
• Do not overlook celiac disease testing in any patient with bilateral occipital calcifications and epilepsy 1
• Do not assume MRI negativity excludes significant pathology in this syndrome 1
• Do not attribute diarrhea solely to epilepsy without investigating for celiac disease, though temporal lobe epilepsy can rarely manifest with diarrhea as an autonomic symptom 3