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Indian Pediatr 2013;50: 973-974 |
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Reversible Skin Hyperpigmentation in
Imerslund-Grasbeck Syndrome
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So Shivbalan and MV Srinath
Sundaram Medical Foundation, Dr Rangarajan Memorial
Hospital, Shanthi Colony, IV Avenue, Annanagar,
Chennai 600 040, Tamil Nadu, India.
Email:
[email protected]
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A 2-year-old girl presented with progressive
hyperpigmentation of both the distal interphalangeal joints of fingers
and toes along with palmar and plantar hyperpigmentation of both hands
and feet for the last one year with no other associated symptoms.
Clinically, her weight (13.5 kg), height (91 cm) and developmental
assessment were appropriate for age. Her other systemic examination but
for her skin pigmentation were all normal. Investigations were not
contributory, other then a low vitamin B 12
level (84.2 pg/mL) and mild megaloblastic picture in bone marrow. A
diagnosis of Imerslund-Grasbeck syndrome (IGS) was considered and was
treated with intramuscular injection of 1000 µg methylcobalamin daily
for 7 days, followed by weekly injections for 1 month and then oral
doses of 1000 µg daily. With therapy, there was a significant change in
10 days time and there was total resolution of skin lesion in a month’s
time. She was advised to have lifelong daily therapy with 1000 µg oral
methylcobalamin.
Hyperpigmentation due to vitamin B 12
deficiency appears only in patients whose skin is normally pigmented,
hence may not be a feature in Caucasians, whereas it is more common in
darker-skinned patients. In Indian children, isolated mucocutaneous
lesions could be one of the earliest signs of B12
deficiency [1] that may predate other systemic manifestations. IGS
should be considered in any individual with macrocytic anemia, reduced
serum B12 levels and
proteinuria. This child with IGS had only skin manifestation on
presentation, probably with time haematological manifestations could
have surfaced, as evidenced by the marrow revealing megaloblastic
changes despite other haematological indices being normal. Life-long
treatment with vitamin B12
is necessary for IGS, which alleviates hematologic, gastrointestinal and
CNS symptoms except proteinuria [2]. High oral doses of B12
(1000 µg and 2000 µg) is safe, acceptable and as effective as
intramuscular administration [3,4]. Oral treatment is based on the
finding that in larger doses, sufficient amounts are absorbed even in
the absence of intrinsic factor.
Available literature suggests that, pigmentary
changes remain unresponsive with vitamin B 12
replacement in IGS as was observed in two Chinese siblings [5]. This
child with vitamin B12
replacement had complete resolution of skin pigmentation but her
proteinuria persisted even on follow up for 3 years.
To conclude, a diagnosis of vitamin B 12
deficiency has to be considered in any case of isolated skin
hyperpigmentation.
References
1. Jadhav M., Webb JK, Vaishnava S, Baker SJ. Vitamin
B12 deficiency in Indian infants. A clinical syndrome. Lancet.
1962;2:903-7.
2. Grasbeck R., Tanner SM. Juvenile selective vitamin
B12 malabsorption: 50 years after its description – 10 years of genetic
testing. Pediatr Res. 2011;70:222-8
3. Nyholm E, Turpin P, Swain D, Cunningham B, Daly S,
Nightingale P, et al. Oral vitamin B12 can change our practice.
Postgrad Med J. 2003;79:218-20.
4. Vidal-Alaball J, Butler CC, Cannings-John R,
Goringe A, Hood K, McCaddon A, et al. Oral vitamin B12 versus
intramuscular vitamin B12 for vitamin B12 deficiency. Cochrane Database
Syst Rev CD004655 (2005). doi:10.1002/14651858.CD004655.pub2
5. Lin SH, Sourial NA, Lu KC, Hsueh EJ.
Imerslund-Grasbeck syndrome in a Chinese family with distinct skin
lesions refractory to vitamin B12. J Clin Pathol. 1994;47:956-8.
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