Gerneral hypertrichosis can be due to porphyria
Information on hypertrichosis and hair removal treatments
Generalized but not necessarily confluent hypertrichosis is often associated with a class of disorders known as porphyrias, where the porphyrin precursors of heme synthesis accumulate as a result of an enzymic defect. It is a systemic disease and can occur sporadically as well as be autosomal inherited. Their presentation often requires provoking agents like chemicals.
‘Porphyria cutanae tarda’, the most common type of porphyria, shows up as a mechanobullous eruption, most prominent in sun exposed areas, that heals with milia and variable hyperpigmentation. Temples, cheeks, eyebrows and hairlines are the most common and predominant sites of hypertrichosis in porphyria and in one series it was found to be 63 percent. Sometimes it may appear on the trunks and extremities. It can range from mild to extensive, particularly, in the temple areas.
Porohyria cutanae tarda is secondary to an inherent deficiency in uroporphyrinogen decarboxylase that, depending on the extent and distribution of the deficient enzyme, may either cause symptoms de novo or require a provoking agent such as alcohol or estrogen.
Uroporphyrinogen decarboxylase is a cytosolic enzyme coded on chromosome 1 that acts as a catalytic agent in the sequential removal of four of the carboxymethyl side chains of uroporphyrinogen to yield coproporphyrinogen. Most cases of porphyria cutanae tarda are sporadic but an autosomal dominant mode of inheritance has also been suggested. The hemochromatosis gene has been suggested as contributing to the patogenesis of porphyria cutanae tarda. Some chemicals such as particularly hexachlorobenzene and chlorinated phenol can cause porphyria cutanae tarda in all those who are exposed to it.
The most well known case of this disorder occurred in Turkey where children ate wheat contaminated with the fungicide hexachlorobenzene and developed porphyria cutanae tarda. The hypertrichosis was so severe that they were called “monkey’s children”. In these cases the cutaneous manifestation of porphyria cutanae tarda and hypertrichosis generally disappeared within a month of discontinuation of exposure to hexachlorobenzene.
Hepatoerythropoetic porphyria is a form of porphyria cutanae tarda that may also be a manifestation of benign or malignant hepatic tumors. It is an autosomal recessive and severe form of homozygous uroporphyrinogen decarboxylase deficiency that appears in early childhood with marked photosensitivity along with blisters and scars and usually facial hypertrichosis and dark urine.
The diagnosis of porphyria cutanae tarda is confirmed in all these conditions by the finding of increased urine uroporphyrins and urine uroporphyrin to coporo porphyrin ratio of greater than 3:1. In hepatoerythropoetic porphyria, erythrocyte protoporphyrin, urine porphyrin and fecal coprophorpjyrin are increased.
A porphyria cutanae tarda – like bullous eruption may be induced in patients with chronic renal failures on hemodialysis or in those taking nalidixic acid, furosemide or tetracycline. Generally hypertrichosis is not seen in patients with these types of porphyria cutanae tarda and urine porphyrins are usually normal. However, there is a class of patients who, after hemodialysis, develop full clinical porphyria cutanae tarda type disorders, across the spectrum and who usually have abnormal porphyrins.
Variegate porphyria is another type which shows the cutaneous features and hypertrichosis of porphyria cutanae tarda. This is an inherited abnormality of protoporphyrinogen oxidase, which is widely present among South African whites and features acute and frequent porpyria-like gastrointestinal and neuropsychologic symptoms. These features appear after exposure to provoking drugs, such as, barbituarates and sulfamides. Diagnosis is usually by finding urine coprophyrin greater than uroporphyrin with increased stool protoporphyrin and coproporphyrin.
Congental erythropoeitic porphyria is a rare autosomal recessive genetic disturbance in porphyrin metabolism that mainly affects the hematopoeitic system. Severe cutaneous photosensitivity to ultra violet light, since birth, is its primary feature and is the reason for the pain on sun exposure and vesicular and bullous lesions that cause scarring, hyperpigmentation and hypopigmentation. This extreme photo sensitivity is due to ultra violet excitation of the porphyrins accumulated on the skin. The ultra violet light not only causes scarring but eventually causes hypertrichosis on areas exposed to the sun.
This hypertrichosis, which is often quite extensive, generally appears at around the age of 5 or 6 years. Excessive hair growth is likely to be more on the limbs and trunks than on the face. The hair may be soft, downy or coarse and is usually pigmented. The density of hair is generally low-the growth being sparse.
Congental erythropoeitic porphyria is caused by a defect of uroporphyrinogen III synthase with accumulation of uroporphyrin I and extreme hemolysis. The color of the urine is pink due to increased excretion of porphyrin. The bones and teeth, which are brown in color, fluoresce red on exposure to Wood’s light. Peripheral and vertebral fractures and bone pain are common and ostopenia and sclerotic lesions may be observed.