Systemic mastocytosis and bone involvement in a cohort of 75 patients.
OBJECTIVE
To investigate bone involvement in a large cohort of systemic mastocytosis (SM) patients, and evaluate the efficacy of bisphosphonate therapy.


METHODS
From 2000 to 2004, 75 patients with SM according to WHO criteria underwent skeletal x-rays and bone mineral density (BMD) assessment. Sequential BMD assessments were performed in nine patients treated with bisphosphonate (mean follow-up 65 months).


RESULTS
37 patients (49%) had bone involvement according to both x-rays and BMD evaluations: osteoporosis (23 patients, 31%, mean lumbar spine T score: -3 SD), with vertebral fracture (13 patients, 17%), axial skeleton osteosclerosis (six patients, 8%), mixed patterns (three patients), osteopenia with pre-existing fractures (four patients) and focal osteolytic lesion (one patient). Blood count abnormalities were associated with osteosclerosis (p=0.005). In nine patients with osteoporosis and bisphosphonate therapy, mean lumbar spine BMD increased from 0.83 to 0.92 g/cm(2) (+11.1%; ie, +2.05% per year) without recurrence of vertebral fracture.


CONCLUSIONS
Half of adult patients with SM have bone involvement. Osteoporosis is the most prevalent bone manifestation in SM (31%). Bisphosphonate therapy seems efficient to improve lumbar spine BMD during SM-related osteoporosis. Spine x-ray and BMD should be performed in all SM patients to detect those who may benefit from anti-osteoporotic therapy.
Barete
S
S
AP-HP, Dermatology and Allergy Department, Université Pierre et Marie Curie, Tenon Hospital, 4 rue Chine, Paris 75020, France. stephane.barete@psl.aphp.fr
Assous
N
N
de Gennes
C
C
Grandpeix
C
C
Feger
F
F
Palmerini
F
F
Dubreuil
P
P
Arock
M
M
Roux
C
C
Launay
J M
JM
Fraitag
S
S
Canioni
D
D
Billemont
B
B
Suarez
F
F
Lanternier
F
F
Lortholary
O
O
Hermine
O
O
Francès
C
C
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density / Q000187:drug effects; D050071:Bone Density Conservation Agents / Q000627:therapeutic use; D004164:Diphosphonates / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008159:Lumbar Vertebrae / Q000503:physiopathology; D008297:Male; D034721:Mastocytosis, Systemic / Q000150:complications* / Q000503:physiopathology; D008875:Middle Aged; D010024:Osteoporosis / Q000188:drug therapy / Q000209:etiology* / Q000503:physiopathology; D055815:Young Adult
D050071:Bone Density Conservation Agents; D004164:Diphosphonates