An occult cause of infantile spasms: Vitamin B12 deficiency. A case report and review of literature

Vitamin B12 deficiency in exclusively breastfed infants is an important problem in developing countries. Vitamin B12 deficiency is associated with a wide spectrum of clinical manifestations. Few cases of vitamin B12 deficiency have been reported as the cause of infantile spasms. We report the case of a 6-month-old boy diagnosed with infantile spasms associated with vitamin B12 deficiency caused by nutritional inadequacy in the mother. He was observed to have head nods and flexor limbs spasms which appeared in clusters. Psychomotor development was normal. The serum vitamin B12 level was low and results of electroencephalography (EEG) indicated modified hypsarrhythmia. His symptoms resolved after synthetic adrenocorticotropic hormone (ACTH) and vitamin B12 treatment. The EEG was completely normal after the first month and sixth month of treatment. In addition to ACTH and vitamin B12 treatment, following antiepileptic drug treatment was not initiated. During 21 months’ follow up he is seizure-free and his neurological development is age-appropriate. This case of a 6 month-old infant with infantile spasms due to vitamin B12 deficiency seems to be a striking because of only with vitamin B12 and ACTH treatment the patient became seizure-free. Vitamin B12 deficiency may be a treatable cause of infantile spasms and should be considered in the associated cause of infantile spasms especially if nutritional inadequacy in the mother. Neurology Asia 2016; 21(3) : 275 – 278 Address correspondence to: Assoc.Prof. Nihal OLGAC DUNDAR, Department of Pediatric Neurology, Izmir Tepecik Education and Research Hospital, Yenisehir 35120, Izmir/ Turkey. Tel: +902324696969, E-mail: [email protected] INTRODUCTION Infants of vitamin B12 deficient breastfeeding mothers, or infants receiving low amounts of animal-source foods, may be vulnerable to vitamin B 12 deficiency between 6 and 12 months of age. Vitamin B12 deficiency in infant is associated with a wide spectrum of clinical manifestations. These include macrocytic anemia, failure to thrive, irritability, lethargy, hypotonia, developmental delay, psychomotor delay, regression, tremor, convulsions and coma. Less specific manifestations include pallor, vomiting, diarrhea, edema and apathy. Moreover, neurologic changes often occur in the absence of hematologic abnormalities. Few cases of vitamin B12 deficiency have been reported as the cause of infantile spasms. We report the case of a 6-month-old boy diagnosed with infantile spasms associated with vitamin B12 deficiency caused by nutritional inadequacy in the mother. CASE REPORT A 6 month-old exclusively breastfed boy was admitted to hospital with brief head nods and symmetric limbs contractions over a period of 10 days. He was the second child of nonconsanguineous parents. He was born full term after a normal pregnancy. His birth weight was 2750 gr (25th percentile), length 47 cm (50th percentile) and head circumference was 35 cm (50th percentile). On physical examination, the child had the following growth parameters; 7.5 kg (10-25th percentile), height 69 cm (25-50th percentile) and head circumference 43 cm (25-50th percentile). He was observed to have head nods and flexor limbs spasms which appear in clusters. Psychomotor development was normal: he was following moving things with eyes and responding to affection. He was achieved trunk control at age 5 months. There were no organomegaly and dysmorphic features. CASE REPORTS Neurology Asia September 2016 276 Hemoglobin level, leukocyte and platelet counts were 11.5 g/dL, 14×10/mm, and 308×10/ mm respectively. Mean corpuscular volume, red blood cell count, and hematocrit were 76.1 fL, 4.34×10/mm, and 33% respectively. The serum vitamin B12 level was low at 99.76 pg/mL (reference range 191-663 pg/mL). Serum folate level was 16.01 ng/mL (referencerange 4.6-18.7 ng/mL). Plasma homocysteine was 3.41 μmol/l (reference range 5-12 μmol/l). Iron and ferritin levels, biochemical profile, blood and urine amino acid levels were within normal range. Cranial magnetic resonance imaging was normal. Results of electroencephalography (EEG) indicated modified hypsarrhythmia (Figure 1) and the patient was diagnosed as having infantile spasms associated with vitamin B12 deficiency. Serum vitamin B12 level of the mother was low at 40 pg/ml. The mother was also diagnosed to have vitamin B12 deficiency and she was referred to internal medicine physicians. The patient received intramuscular synthetic adrenocorticotropic hormone (ACTH) treatment 25 IU twice a week, total of 12 doses and intramuscular vitamin B12 treatment 100 mcg daily for a week, then given 100 mcgevery other day for a week, and then given 100 mcg twice a week. After this regimen, he was given 100 mcg monthly for 3 months. His symptoms resolved after ACTH and vitamin B12 treatment. The EEG was completely normal after the first month and sixth months of treatment (Figure 2). A month after vitamin B12 treatment, vitamin B12 level increased to Figure 2. Normal EEG after treatment Figure 1. EEG showing modified hypsarrhythmia