Skeletal implications of isolated bone
marrow mastocytosis

In the article on the isolated bone marrow mastocytosis
(IBMM) as an underestimated subvariant of indolent
systemic mastocytosis (ISM), Zanotti et al.1 reported that
54.7% of patients with unexplained/recurrent anaphylaxis
or severe allergic reactions were found to be suffering
from IBMM. They conclude that the incidence of
IBMM can be frequently underestimated, especially in
the face of a lack of collaboration among medical specialities,
while early recognition can potentially reduce lifethreatening
events and/or severe skeletal complications.
Although this is an extremely interesting finding
depicting the problem of unrecognized IBMM, the
Authors do not provide an acceptable level of information
regarding the skeletal problems of the patients. Since
bone densitometry (BMD) was performed in all patients
and X-rays in selected cases, it would be helpful for the
reader to know the skeletal implications of these subjects.
Osteoporosis or osteopenia is by far the most frequently
observed pathological skeletal sign in systemic
mastocytosis reported in more than one-third of all
patients, while osteolysis and osteosclerosis can occur,
even simultaneously, in the same patient. In addition,
osteoporosis can be the only presentation in IBMM;
specifically among men IBMM can be found in up to 9%
of patients with idiopathic osteoporosis.2 Furthermore,
fractures, mostly vertebral, have been reported in approximately
15% of all patients with systemic mastocytosis.3
Serum tryptase is currently considered the test of
choice in the initial assessment of suspected systemic
mastocytosis cases.4 However, its cost-effectiveness in
the evaluation of secondary osteoporosis is yet to be
defined due to the lack of data regarding the real incidence
of the disease among osteoporotic patients. It
would be very important to know whether the Authors
can confirm or not a low BMD and/or pathological fractures
in patients with IBMM, especially among young
patients. In the former case, the importance of considering
the diagnosis of IBMM in subjects with a low BMD
and/or fractures and a history of recurrent allergic reactions
would be highlighted.

http://www.haematologica.org/cgi/reprint/96/4/e27?rss=1