Oral phosphate binders in the treatment of pseudoxanthoma elasticum.
BACKGROUND
Pseudoxanthoma elasticum (PXE) is a systemic connective tissue disorder involving elastic fiber calcification and fragmentation with major clinical manifestations occurring in the cutaneous, ocular, and cardiovascular systems. Normalization of the serum calcium-phosphate product through hemodialysis in a previous patient with perforating periumbilical PXE and elevated serum phosphate resulted in regression of skin lesions.


OBJECTIVE
We sought to study the effect of pharmacologically limiting the intestinal absorption of phosphate in patients with PXE.


METHODS
Patients received baseline skin examinations, target skin lesion evaluation, and photography; renal function tests and serum calcium and phosphate levels; urine calcium, phosphate, and creatinine levels; skin biopsy; and eye examinations and indocyanine-green angiography. Patients were treated with aluminium hydroxide tablets or liquid and returned every 2 to 4 months for skin photography and lesion evaluation. Repeated skin biopsies were performed on clinically improved target sites. Ophthalmologic evaluation was obtained at yearly intervals.


RESULTS
Of 6 patients, 3 showed significant clinical improvement of skin lesions and all 3 of these patients showed histopathologic regression of disease in their target lesions. No deterioration of eye disease was seen in any of the 6 patients at 1-year follow-up.


CONCLUSIONS
Our results demonstrate that the calcification seen in PXE may be reversible in some patients. This could hold true for eye and vascular lesions and for skin. Further studies supporting these results could reveal the first real treatment option for PXE.
Sherer
Daniel W
DW
Mount Sinai School of Medicine, New York, New York, USA.
Singer
Giselle
G
Uribarri
Jaime
J
Phelps
Robert G
RG
Sapadin
Allen N
AN
Freund
K Bailey
KB
Yanuzzi
Lawrence
L
Fuchs
Wayne
W
Lebwohl
Mark
M
D000328:Adult; D000536:Aluminum Hydroxide / Q000008:administration & dosage*; D002118:Calcium / Q000097:blood; D005765:Gastrointestinal Agents / Q000008:administration & dosage*; D006801:Humans; D007408:Intestinal Absorption; D008875:Middle Aged; D010758:Phosphorus / Q000097:blood; D011561:Pseudoxanthoma Elasticum / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology
D005765:Gastrointestinal Agents; D010758:Phosphorus; D000536:Aluminum Hydroxide; D002118:Calcium