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Show journal of Neiim- Ophthalmology 14( 1): 9- 11, 1994. © 1994 Raven Press, Ltd., New York Intracranial Hypertension in a Dieting Patient Michael Sirdofsky, M. D., Jorge Kattah, M. D., and Pablo Macedo, M. D. We report a case of encephalopathy with paranoid psychosis in association with intracranial hypertension. This occurred in a patient whose diet consisted almost solely of walnuts, ginseng tea, and vitamin A supplements. The patient was found to be severely iron- and vitamin B12- deficient. She was vitamin A toxic. Venous sinus thrombosis was also present. Symptoms remitted with serial lumbar punctures, normalization of diet, and repletion of vitamin B12 and iron stores. Physicians should be alerted to the possibility of a potentially confusing clinical presentation with coexistent and seemingly mutually exclusive neruologic conditions in patients with extremely restricted or fad diets. Key Words: Pseudotumor cerebri- Diet- Iron- deficiency anemia- Venous sinus thrombosis. From the Department of Neurology, Georgetown University Hospital, Washington, D. C., U. S. A. Address correspondence and reprint requests to Dr. Michael Sirdofsky, Department of Neurology, Georgetown University Hospital, 3800 Reservoir Road, NW, Washington, D. C., 20007, U. S. A. CASE REPORT A 37- year- old female presented with a history of increasing headache, confusion, paranoid ideation, and transient obscuration of vision. Symptoms were slowly p r o g r e s s i v e over several months. For years the patient ate a vegetarian diet. Within the last 2 years her diet consisted almost solely of walnuts, ginseng tea, and vitamin A supplements. Progressive personality changes, confusion, and headaches brought her to medical attention. Evaluation revealed a confused patient who was slow to respond. Marked paranoid psychosis was found. Grade IV papilledema was present on fun-duscopic examination. Peripapillary and midpe-riphery hemorrhages were present in the retina. Other neurophthalmologic findings were normal. Formal neuropsychometric testing revealed a verbal IQ of 127. Performance IQ was low average. Memory was unaffected. A computed tomography ( CT) scan of the brain, with and without contrast, was normal. Magnetic resonance imaging ( MRI) of the brain revealed increased signal on Tl- weighted scans from the coronal suture to the torcular ( Fig. 1). MRI angiography revealed lack of filling of the posterior third of the superior sagittal sinus ( Fig. 2). Lumbar puncture showed an opening pressure of 500 mm of water. There were 40/ mm3 red blood cells and 2/ mm3 white blood cells. Protein was 19 mg/ dl and glucose was 91 mg/ dl. Cerebrospinal fluid VDRL test and cryptococcal antigen were negative. Oligoclonal bands were absent. Hematocrit was 24%. Mean corpuscular volume was 63 ( normal: > 80), and mean corpuscular hemoglobin was 19 ( normal: > 27). The smear revealed marked hypochromia and microcytosis. Reticulocyte count was 12.6%. Serum iron was 18 ( normal: 50- 132). Prothrombin time, partial thromboplastin time, protein C, and protein S were normal. Antinuclear 10 M. SIRDOFSKY ET AL. FIG. 1. Increased T1- weighted signal in the posterior third of the superior sagittal sinus suggesting reduced filling ( arrow). antibody was speckled 1: 40. ENA was negative. Vitamin A level was 110 mg/ dl ( normal: 30- 95). Vitamin B12 level was 138 pg/ ml ( normal > 200). Schilling's test, part one, was normal. The patient was treated with serial lumbar punctures, Diamox for 6 months, and vitamin B] 2 and iron supplements, and a normal diet was established. Mental status improved to normal within several months. The patient is once again functioning as a lawyer without difficulty. Funduscopic examination approximately 1 year later revealed only minimal residual disc edema. Serial MRI scans revealed improvement in the patency of the sagittal sinus. DISCUSSION Pseudotumor cerebri is a syndrome of increased intracranial pressure and papilledema not associated with focal neurologic signs. Criteria for diagnosis includes elevated cerebrospinal fluid pressure of > 200 mm of water. There should be normal cellular and biochemical components of the spinal fluid. Symptoms and signs should be restricted to those of increased intracranial pressure ( 1). Our initial diagnostic impression in this case was pseudotumor cerebri. However, the associated encephalopathy and psychosis suggested a toxic state. Obesity and pseudotumor cerebri are often associated. Paradoxically, this patient, who was of normal body habitus, engaged in an extremely restrictive diet, designed by herself, in order to lose weight. Our investigation identified vitamin A toxicity, vitamin B12 deficiency, and iron- deficiency anemia as the most striking metabolic abnormalities involved. Venous sinus thrombosis contributed to the development of intracranial hypertension. Iron- deficiency anemia alone has been well reported in association with intracranial hypertension. Prior to 1963, 44 cases were described. The hemoglobin was usually 30- 70% of normal. Of 29 autopsied cases, however, no mention was made of venous sinus thrombosis ( 2). A recent publication cites three cases of venous sinus thrombosis in association with iron- deficiency anemia ( 3). Proposed mechanisms include cerebral anoxia, secondary to iron- dependent cytochromes, increased cerebral blood flow, secondary to marked anemia, and anoxic anemia, secondary to decreased oxygen- carrying capacity of the blood. This syndrome, formerly named " chlorosis," responds favorably to blood transfusion. Walnuts contain phytates and polyphenols. Both of these compounds act as potent inhibitors of iron absorption. Walnut- based diets lead to iron- deficiency anemia in third world countries, where large amounts of nuts are consumed on a regular basis ( 4). In our patient, dietary lack of iron intake was compounded by her consumption of walnuts, which resulted in severe iron deficiency. FIG. 2. Magnetic resonance imaging angiography reveals lack of filling of the posterior third of the superior sagittal sinus ( arrow). I Neuro- Ophtlmlmol, Vol. 14, No. 1, 1994 INTRACRANIAL HYPERTENSION IN DIETER 11 In addition to the above- listed factors, our patient was taking on average, 15,000 to 20,000 units of vitamin A per day. Intracranial hypertension has been reported with doses as low as 25,000 units per day. The vitamin A requirement in nonpregnant females is 4,000 units per day. Children fed fish liver oils and Arctic explorers who ate large amounts of polar bear liver, rich in vitamin A, have developed intracranial hypertension ( 5). The mechanism whereby vitamin A toxicity causes intracranial hypertension is not known. However, vitamin A toxicity has been shown to be associated with histologic changes in the arachnoid granulations ( 6). Finally, ginseng root has been reported to have an estrogenlike effect, with postmenopausal bleeding described in users. This is intriguing, given the association of estrogens and intracranial hypertension, and may represent one more risk factor in this patient attributable to her diet ( 7). Although abnormal cognitive function has been reported in patients with pseudotumor cerebri, paranoid psychosis is not mentioned ( 8). It is clear that the mental status changes in this case were too severe to be solely related to the intracranial pressure increment associated with pseudotumor. In summary, encephalopathy, marked paranoid psychosis, ocular hemorrhages, papilledema, and venous sinus thrombosis were found in our patient. Venous sinus thrombosis is likely the major factor in this patient's intracranial hypertension, with recanalization of the sinus probably accounting for her improvement. However, multiple risk factors including vitamin A toxicity, iron deficiency, and B12 deficiency coexisted. Physicians should be aware of a possibly confounding array of risk factors, which may be independently contributing to the clinical presentation when encountering patients on fad diets. REFERENCES 1. Fishman RA. Cerebrospinal fluid in diseases of the nervous system. Philsdelphia: WB Saunders; 1980: 128. 2. Capriles LF. Intracranial hypertension and iron- deficiency anemia. Arch Neurol 1963; 9: 150. 3. Stehle G, Buss J, Heene DL. Noninfectious thrombosis of the superior sagittal sinus in a patient with iron deficiency anemia. [ Letter] Stroke 1991; 22: 414. 4. Macfarlane BJ, Bezwoda WR, Bothwell TH, et al. Inhibitory effect of nuts on iron absorption. Am J Clin Nutr 1988; 270- 4. 5. Bhettay EM, Bakst CM. Hypervitaminosis A causing benign intracranial hypertension. S Afr Med ] 1988; 74: 584- 5. 6. Hayes KC, McCombs HL, Faherty TP. The fine structure of vitamin A deficiency. II. Arachnoid granulations and CSF pressure. Brain 1971; 94: 213- 4. 7. Hopkins MP, Androff L, Benninghoff AS. Ginseng face cream and unexplained vaginal bleeding. Am ] Obstet Gynecol 1988; 159: 1121- 2. 8. Sorensen PS, Thomsen AM, Gjerrig F. Persistent disturbances of cognitive functions in patients with pseudotumor cerebri. Acta Neurol Scand 1986; 73: 264- 8. J Neuro- Ophthalmol, Vol. 14, No. 1, 1994 |