Pigmentation in vitamin B12 deficiency masquerading Addison's pigmentation: A rare presentation

Area of Science:

• Endocrinology
• Dermatology
• Hematology

Background:

• Addison's disease is a common consideration for patients presenting with generalized weakness, weight loss, and hyperpigmentation.
• Hyperpigmentation can manifest in various forms and locations, including the palms, soles, oral mucosa, and gluteal region.

Observation:

• A 35-year-old female presented with generalized weakness, weight loss, and progressive hyperpigmentation affecting multiple body areas.
• Initial workup for Addison's disease was negative, with no evidence of hypocortisolemia.
• The patient was found to have megaloblastic anemia and low serum vitamin B12 levels, attributed to poor dietary intake.

Findings:

• Vitamin B12 deficiency was identified as the cause of the patient's hyperpigmentation.
• Skin biopsy revealed increased melanin in the stratum spinosum and basal layer.
• Hyperpigmentation resolved completely following vitamin B12 supplementation, indicating a direct link.

Implications:

• This case highlights vitamin B12 deficiency as a potential, often overlooked, cause of hyperpigmentation.
• Understanding this association can aid in diagnosing and managing similar cases, preventing unnecessary investigations for Addison's disease.
• The findings suggest that vitamin B12 plays a role in regulating melanin synthesis, warranting further research into the underlying mechanisms.