Porphyria in childhood

Dermal eosinophilic infiltrate in junctional epidermolysis bullosa

Junctional epidermolysis bullosa (JEB) is a rare genodermatosis characterized by a split in the lamina lucida usually because of mutations in LAMA3, LAMB3 and LAMC2 resulting in absence or reduction of laminin-332. Rare subtypes of JEB have mutations in COL17A1, ITGB4, ITGA6 and ITGA3 leading to reduction or dysfunction of collagen XVII, integrin α6β4 and integrin α3. The classic finding under light microscopy is a paucicellular, subepidermal split. We describe the unusual presence of an eosinophilic infiltrate in the bullae and subjacent dermis in a neonate with JEB, generalized intermediate (formerly known as non-Herlitz-type JEB), discuss the histologic differential diagnosis for a subepidermal blister in a neonate, review the literature regarding cases of epidermolysis bullosa (EB) presenting with inflammatory infiltrates, and discuss mechanisms to explain these findings. This case highlights that eosinophils can rarely be seen in EB and should not mislead the dermatopathologist into diagnosing an autoimmune blistering disorder.

Environmental dermatology in childhood: photosensitivity

Recently, sunlight-induced damage of healthy human skin, including skin malignancies and a large scale of photodermatoses representing a diverse group of diseases, have increased in childhood as a result of unfavorable environmental changes. This article yields an overview of the diagnosis, the clinical features and the treatment of these conditions and disorders and also reveals perspectives. Some diseases are more frequent in the pediatric population than in adulthood, whereas others heal spontaneously during adolescence and vice versa. The majority of cases are idiopathic photodermatoses, mainly polymorphic light eruption. Photosensitivity may be an early symptom of genetic disorders, such as porphyria, or very rare genophotodermatoses. Photosensitivity, secondary to topical or systemic external agents as well as photoexacerbated dermatoses, is not so frequent in childhood. Effective photoprotection is crucial.

Congenital erythropoietic porphyria (Günther's disease): two cases with very early prenatal manifestation and cystic hygroma

Congenital erythropoietic porphyria (CEP) or Günther's disease is the rarest form of the porphyrias. The disease is usually diagnosed at birth or during early infancy, but rarely in utero. We describe here the first two cases of very early prenatal expression of CEP with cystic hygroma diagnosed at 14 weeks in the first fetus and at 19 weeks in the second. Both fetuses presented with severe nonimmune hydrops fetalis as early as 19 and 22 weeks, associated with intrauterine growth retardation, hyperechogenic kidneys and bones. Amniotic fluid was dark brown and uro- and coproporphyrin I was dramatically increased. Molecular screening of the CEP gene detected heterozygous C73R mutation in both fetuses, the other parental mutation being as yet unknown.

Erythropoietic and hepatic porphyrias

Porphyrias are divided into erythropoietic and hepatic manifestations. Erythropoietic porphyrias are characterized by cutaneous symptoms and appear in early childhood. Erythropoietic protoporphyria is complicated by cholestatic liver cirrhosis and progressive hepatic failure in 10%, of patients. Acute hepatic porphyrias (delta-aminolaevulinic acid dehydratase deficiency porphyria, acute intermittent porphyria, hereditary coproporphyria and variegate porphyria) are characterized by variable extrahepatic gastrointestinal, neurological-psychiatric and cardiovascular manifestations requiring early diagnosis to avoid life-threatening complications. Acute hepatic porphyrias are pharmacogenetic and molecular regulatory diseases (without porphyrin accumulation) mainly induced by drugs, sex hormones, fasting or alcohol. The disease process depends on the derepression of hepatic delta-aminolaevulinic acid synthase following haem depletion. In contrast to the acute porphyrias, nonacute, chronic hepatic porphyrias such as porphyria cutanea tarda are porphyrin accumulation disorders leading to cutaneous symptoms associated with liver disease, especially caused by alcohol or viral hepatitis. Alcohol, oestrogens, haemodialysis, hepatitis C and AIDS are triggering factors. Porphyria cutanea tarda is the most common porphyria, followed by acute intermittent porphyria and erythropoietic protoporphyria. The molecular genetics of the porphyrias is very heterogenous. Nearly every family has its own mutation. The mutations identified account for the corresponding enzymatic deficiencies, which may remain clinically silent throughout life. Thus, the recognition of the overt disorder with extrahepatic manifestations depends on the demonstration of biochemical abnormalities due to these primary defects and compensatory hepatic overexpression of hepatic delta-aminolaevulinic acid synthase in the acute porphyrias. Consequently, haem precursors are synthesized in excess. The increased metabolites upstream of the enzymatic defect are excreted into urine and faeces. The diagnosis is based on their evaluation. Primary enzymatic or molecular analyses are noncontributary and may be misleading. Acute polysymptomatic exacerbations accompany a high excretory constellation of porphyrin precursors delta-aminolaevulinic acid and porphobilinogen. Homozygous or compound heterozygous variants of acute hepatic porphyrias may already manifest in childhood.

Childhood-onset porphyria cutanea tarda: successful therapy with low-dose hydroxychloroquine (Plaquenil)

We describe a 4-year-old girl with a spontaneous blistering disorder that was consistent with porphyria cutanea tarda (PCT). There was no familial history of the disease or any obvious causative factors present. Oral hydroxychloroquine (3 mg/kg) was given twice weekly along with vitamin E (200 U/d) as an antioxidant. Within 6 weeks, marked decreased blistering occurred and by 12 weeks no blistering was evident. Despite clinical improvement and tolerance of hydroxychloroquine, urinary uroporphyrin, aspartate aminotransferase, and ferritin levels continued to rise reaching peak levels at 16 weeks of therapy. Near total biochemical remission was observed at 40 weeks and all therapy was discontinued at 60 weeks.