The
porphyrias can be grouped conveniently by their presenting symptoms. Acute intermittent neurological symptoms of
neuritis,
abdominal pain and
psychoses may occur in
acute intermittent porphyria,
hereditary coproporphyria and variegata
porphyria. Increase of the
porphyrin precursors delta-aminolaevulinic
acid and
porphobilinogen may be observed in the urine during attacks (Watson-Schwartz test). Patients with acute symptoms of photosensitivity with
burning pain and oedema within short exposure periods may have
erythropoietic protoporphyria, with high erythrocyte and stool
protoporphyrins, erythropoietic
coproporphyria, and in the last few years of life the more recently described
hepatoerythropoietic porphyria. Symptoms of chronic photosensitivity include;
hyperpigmentation,
hypertrichosis, easy fragility of the skin with
bullae and subsequent
scarring in
porphyria cutanea tarda (PCT), with increased uroporphyrin in the urine and stool;
variegate porphyria with increased
protoporphyrin and coproporphyrin in the stool;
congenital erythropoietic porphyria with an increased copro- and uroporphyrin (isomer I) in the erythrocytes, urine and stool; and
hepatoerythropoietic porphyria in later life, in which the chronic features are similar to PCT. In 1913 Meyer-Betz injected himself with 200 mg haematoporphyrin. Initially, at the higher levels, the symptoms were those of
solar urticaria as observed in
erythropoietic porphyria, but after several months became identical to PCT. A comparison of quantitative
porphyrin analysis (performed on 323 patients with
porphyria) and chromatography provides additional confirmation for the diagnosis.