Preferred Label : Hemangioma-thrombocytopenia syndrome;
CISMeF acronym : KMS;
Type : Other, mainly phenotypes with suspected mendelian basis;
Alternative titles and symbols : KMS; Kasabach-merritt syndrome;
Description : With giant hemangiomas in small children, thrombocytopenia and red cell changes compatible
with trauma ('microangiopathic hemolytic anemia') have been observed. The mechanism
of the hematologic changes is obscure. No evidence of a simple genetic basis has been
discovered. Propp and Scharfman (1966) reported a male infant with thrombocytopenia
associated with a large hemangioma of the right arm and axilla. The patient had low
platelet counts with a markedly diminished platelet survival time and an absence of
platelet agglutinin or complement-fixing antibody. Radiochromate-tagged platelet studies
suggested sequestration in the hemangioma, liver, and spleen. A combination of reticulocytosis
and helmet cells was observed, possibly indicating an associated microangiopathic
hemolytic anemia. The hemangioma eventually regressed with radiotherapy. David et
al. (1983) reported 2 unrelated infants with thrombocytopenia and hemangiomas of the
neck and left knee, respectively, both of whom were treated with corticosteroids without
notable improvement. The hemangioma of the knee ultimately showed slow spontaneous
resolution, but the cervical hemangioma required radiotherapy. Larsen et al. (1987)
reported their 15-year experience managing 6 children with capillary hemangiomas associated
with consumptive coagulopathy. In 3 of their patients, the hemangiomas remained small
for many months and then suddenly enlarged, with the simultaneous appearance of a
hemorrhagic diathesis. The duration of the thrombocytopenia ranged from 5 to 20 months;
a variety of therapies were used. All of the patients eventually experienced resolution
of their lesions and a concomitant reversal of the coagulopathy. Sencer et al. (1987)
reported the case of a newborn infant with splenic hemangioendothelioma with thrombocytopenia,
anemia, and disseminated intravascular coagulation who was successfully treated with
splenectomy. Vellodi and Bini (1988) described a severe hyperkalemia resulting in
'malignant ventricular arrhythmias.' They attributed the hyperkalemia to breakdown
of erythrocytes. Breakdown of platelets is another possible source. Enjolras et al.
(1997) examined biopsy specimens from 15 patients with KMS and concluded that the
vascular lesion underlying KMS is not a 'true,' classic, involuting type of hemangioma
of infancy. It is a different vascular tumor with a resemblance pathologically to
either tufted angioma or kaposiform hemangioendothelioma in association with lymphatic-like
vessels. Enjolras et al. (1997) noted that in KMS, when cessation of platelet consumption
is achieved, the tumoral mass rapidly resolves and the patient enters a biologic and
clinical remission. Thus, in KMS it appears not only that the vascular anomaly triggers
platelet trapping and consumption but that platelet activation inside these lesions
sustains the growth of a cellular tumor component. Szlachetka (1998) reviewed the
approximately 205 reported cases of KMS and discussed the pathophysiology, clinical
manifestations, differential diagnosis, and treatment modalities of the disorder.;
Inheritance : Autosomal dominant;
Prefixed ID : 141000;
Origin ID : 141000;
UMLS CUI : C0221025;
Automatic exact mappings (from CISMeF team)
- Currated CISMeF NLP mapping
- False automatic mappings
- HPO term(s)
- ORDO concept(s)
- Semantic type(s)
- UMLS correspondences (same concept)
