Livedo reticularis due to pellagra in a two year old child.

A two-year-old girl child was admitted with complaints of diarrhoea of one week duration in the paediatric ward. She was referred to the skin OPD for gradually progressive skin rashes on both lower limbs noticed since two days. Dermatological examination revealed finding of livedo reticularis. Dietary history revealed maize forming a significant portion of the child's diet since the age of nine months. The child was treated with a course of Niacin in the form of Nicotinamide 50 mg twice a day for 4 weeks and the parents were advised not to give her maize in the diet. The skin lesions and diarrhoea regressed in duration of two weeks. This is probably the first time that a case of pellagra causing livedo is being reported, that too in a child.

What was known?

Pellagra can occur rarely in children.

Pellagra causes various forms of dermatitis.

Response of pellagra to Niacin supplementation is dramatic.

Introduction

The term livedo was first introduced by Hebra to describe the violet discoloration of skin due to local circulatory disturbance. Though it can occur physiologically in neonates, it is associated with a large number of systemic conditions in later life. Pellagra is caused by deficiency of vitamin niacin and this can occur due to unbalanced diet, malabsorption, disturbances in tryptophan metabolism, certain drugs, Hartnup's disease and rarely carcinoid syndrome. We herein describe a child on predominantly maize diet that developed diarrhoea along with livedo reticularis and responded dramatically to treatment with niacin.

Case Report

A two year old girl child was admitted with complaints of diarrhoea of one week duration in the Paediatric ward. She was referred to the Skin OPD for gradually progressive skin rashes on both lower limbs noticed since two days. There was no history of fever, oral ulcers or any drug intake prior to onset of complaints. The child had attained milestones corresponding to age and vaccination was up to date. Paediatric examination had revealed no features of developmental delay. There was no pallor, icterus or cyanosis. Dermatological examination revealed net like pattern of erythematous to violaceous macules on both legs and buttocks [Figures 1 and 2]. There was no evidence of any other skin or mucosal lesions. Systemic examination was normal. The patient was diagnosed as having livedo reticularis. Over the course of five days the lesions spread to involve the entire lower limbs and buttocks. Antinuclear antibodies, antiphospholipid antibodies, VDRL and cryoglobulins were negative. Ultrasonography of the abdomen and liver function tests were normal. The parents were unwilling for skin biopsy. Keeping in view the diarrhoea, the parents were asked about specific dietary history which revealed maize forming a significant portion of the child's diet since the age of nine months. The child was treated with a course of Niacin in the form of Nicotinamide 50 mg twice a day and the parents were advised not to give her maize in the diet. She was also given multivitamin drops and advised protein rich diet. Within one week time, the diarrhoea and skin lesions had regressed [Figure 3]. So a diagnosis of Livedo reticularis secondary to pellagra was made based on the therapeutic response. Follow up till six months after initial presentation revealed no features of relapse of either the diarrhoea or livedo.

Figure 1

Livedo reticularis on buttocks and lower limbs

Figure 2

Similar lesions on anterior aspect of thighs

Figure 3

Resolution of skin lesions

Discussion

Livedo reticularis is characterized by erythematous to violaceous net pattern on skin, often precipitated by cold. The net like pattern could be due to venous drainage at the margins of skin areas richly supplied by a cone of arteries. It is also suggested that this pattern can result either due to arteriolar disease leading to obstruction to inflow or due to hyperviscosity and obstruction to the outflow of blood in venules.1 Livedo reticularis commonly occurs on legs, but trunk and arms can also be affected.

Livedo reticularis is either idiopathic or secondary. The idiopathic variant usually has onset in neonates and then persists into the adult life. Secondary livedo reticularis mostly is seen in cold exposed women. It can be associated with many systemic conditions like antiphospholipid antibody syndrome, systemic lupus erythematosus, polyarteritis nodosa, syphilis, cryoglobulinemia and can also be secondary to drugs like amantadine, quinidine, minocycline and catecholamines.2 Carcinoid syndrome is another rare possibility where determination of 5 hydroxyindole acetic acid urinary excretion will confirm diagnosis. It has also been seen in associations with conditions like Rheumatic fever and Moya Moya disease.34

Though typically pellagra is an adult disease, it can rarely occur in young children who have faulty diets. It has been seen experimentally that pellagra can develop 50 60 days after starting niacin deficient diet.5 Meat, fish, beans, nuts, poultry and eggs are good sources of niacin in addition to fortified bread, milk, cereals and rice.6 Also 60 mg of dietary tryptophan is converted in human body to 1mg niacin.7 This conversion requires the presence of vitamin B2 and B6. Thus, deficiency of one of these vitamins can also precipitate pellagra in a nutritionally compromised patient.

The diagnosis of pellagra is mainly clinical. Specific laboratory test includes fluorometric assays of urinary metabolites, especially the 2 pyridone to N? methyl niacinamide ratio being less than 2.[8] The specific therapy for adults is oral 300 500 mg niacinamide daily given in divided doses, while in children it could range from 10 200 mg/day. Multivitamins and high quality protein diets are contributory. The skin lesions rapidly clear on niacin replacement, as in our case.

So we had a child with diarrhoea and livedo reticularis which responded to niacin dramatically. There has been no previous report of such a manifestation in literature. Both pellagra and livedo are clinically diagnosed conditions and therapeutic trial with niacin is the final proof as in our case.

What is new?

Livedo reticularis can occur as a manifestation of pellagra.

Pellagra can occur even in small children if predominant jowar diet is taken.