Skin lesions in a patient with Cobalamin C disease in poor metabolic control

Excerpt

Skin lesions (Fig. 1 a) of an 8 year old boy with cobalamic C disease. The diagnosis of cobalamin C disease was confirmed by molecular studies (homozygous pathogenic mutation, c.567dupT in MMACHC gene) after newborn screen showed elevated C3. Treatment with betaine, hydroxocobalmin, and leucovorin was initiated soon after the diagnosis. However, the patient was poorly compliant. At presentation of these lesions, homocysteine was 181.2 μmol/l. Plasma methionine was very low and plasma methylmalonic acid was high (Suppl. Table 1). Patient was on unrestricted diet and his essential amino acid levels were normal (Suppl. Table 2). Home care nursing and school health services were involved to ensure compliance with treatment which consisted of vitamin B12 injections (10 mg/Kg/day intramuscular), betaine (250 mg/Kg in two divided doses), and folinic acid (2.5 mg three times a day). Within a week, lesions improved and healed by 6 weeks. Metabolic parameters showed improving trend with improvement in the lesions (Fig. 1 b-d, Suppl. Table 1). Biopsy of a lesion (Fig. 1 e) showed acanthosis, spongiosis and perivascular lymphocytic and eosinophilic infiltrates (Fig. 1 f).

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