Pseudo porphyria or porphyria cutanea tarda?

Resumen

Manuscripts about pseudoporphyria (PP) and
porphyria cutanea tarda (PCT) are commented here,
emphasizing some gastroenterological relationships
and possible diagnostic challenges or misdiagnosis,
in special for daily practice of primary health care
workers. Batrani et al. described PP associated with
the use of imatinib and manifested by bullae, erosions,
scarring and milia on the dorsum of hands and feet,
in absence of photosensitivity (1). Biopsy sample
showed subepidermal blister, dermal festooning of
papillae and thickened vessels; and the level of urinary
porphyrin was within the normal range (1). Imatinib
has been also associated with PCT; however, in this
patient the diagnosis was consistent with PP (1). Peláez-
Castro et al. reported the first Peruvian case of PP in
a hemodialytic woman with facial hyperpigmentation,
bilateral bullae on the fingers, and some crusts on
the dorsum of hands (2). Biopsy study revealed sub
epidermal blisters, with dermal festooning and mild
lymphocytic infiltrate; however, the normal profiles of
porphyrins allowed confirm the diagnosis of PP (2). This
condition is related to renal failure and hemodialysis,
non-steroidal anti-inflammatory drugs, furosemide,
retinoids, sulphonamides, tetracyclines, dapsone, and
nalidixic acid (1,2). Hypertrichosis, hyperpigmentation,
calcifications and sclerodermoid lesions are
uncommon in PP; however, clinical, histopathological
and immunofluorescence features can mimic PCT (1).
Therefore, normal urinary and plasmatic porphyrins are
mandatory for diagnosis of PP (1,2).