Kasabach-Merritt syndrome: pathogenesis and management

A severe bleeding diathesis in a 6-year-old girl secondary to a composite diagnosis of splenic hemangiomatosis and small bowel lymphangiomatosis

A 6-year-old girl presented with presumed relapse of childhood immune thrombocytopenia. Investigations revealed deranged coagulation parameters, abnormal small bowel thickening, and splenomegaly. A clinically significant bleeding diathesis emerged which was refractory to most hemostatic interventions. Laparatomy revealed a composite diagnosis of splenic hemangiomatosis and small bowel lymphangiomatosis. Splenectomy resulted in complete resolution of the coagulopathy. The diagnosis and management of these conditions is inherently complex and without clear guidance. We discuss our perioperative management of the bleeding diathesis. There is a need for long-term follow-up of the underlying pathologies particularly as potentially useful therapeutic agents have emerged.

Successful treatment of mild pediatric kasabach-merritt phenomenon with propranolol monotherapy

Kasabach-Merritt phenomenon (KMP) is relatively rare in childhood and adolescents with high mortality rate because of its hemorrhagic complications and unresponsiveness to treatments such as corticosteroids, vincristine, intravascular embolization, and/or surgery. Propranolol, a β -adrenergic receptor blocker, has a promising efficacy against vascular tumors such as infantile hemangiomas. But limited and variable data has been reported regarding the role of propranolol in treatment of KMP. We herein reported the successful treatment of mild pediatric KMP with propranolol monotherapy in a case of a five-week-old child with kaposiform hemangioendothelioma with successful treatment of both clinical and hematologic responses. After eight months of follow-up, patient still had stable cutaneous lesion while receiving propranolol monotherapy. Regular hematologic monitoring was done in order to detect any late relapse of the disease. Six months after discontinuation of propranolol, patient has still remained free of hematologic relapse, and primary cutaneous lesion has become a pale pink, 1 cm sized skin lesion.

Periocular hemangiomas and lymphangiomas

Infantile hemangiomas are the most common benign tumor of childhood. Lymphangiomas are benign hamartomatous vascular tumors. Both lesions can be problematic when located in the periocular region. Pediatricians must be familiar with the characteristics of each which would necessitate referral to an ophthalmologist or other subspecialist for evaluation, including obstruction of the visual axis which can lead to amblyopia of the affected eye. Additional potential complications include proptosis, ocular motility limitation, optic nerve injury, and poor eyelid closure with or without corneal surface disease. All children with periocular hemangiomas or lymphangiomas should be referred to an ophthalmologist for further evaluation.

Successful management of a small infant with Kasabach-Merritt phenomenon using vincristine: a case report

Kasabach-Merritt Phenomenon (KMP) is characterized by profound thrombocytopenia, microangiopathic haemolytic anaemia and consumptive coagulopathy in the presence of an enlarging vascular lesion. The syndrome usually develops in infancy and is associated with a high morbidity and mortality rate. We report a case of successful management of refractory KMP in a very small infant with the use of vincristine. A female neonate was born with a giant haemangioma on the right thigh and soon presented with coagulopathy and severe thrombocytopenia due to rapid enlargement of the lesion. The condition proved refractory to steroids and propranolol, and the baby was on supportive therapy with daily administration of red blood cells, platelets and cryoprecipitate. Treatment failure and the risk of serious bleeding led to the decision of starting vincristine on the 45th day of life. During the first week of therapy, haematological parameters improved rapidly, and on the second week, the infant had no need for blood products. By the third week of treatment, platelet count and fibrinogen levels had normalized, and the tumour size was dramatically reduced. The infant completed therapy without experiencing any side-effects and had no relapse during the two years that followed. Vincristine proved to be safe, effective and well tolerated in the treatment of this young baby with severe form of KMP. The report, also, highlights the need for considering vincristine early in the management of KMP, especially in cases of rapidly expanding haemangiomas that raise the suspicion of possible malignant lesions (kaposiform haemangioendothelioma/tufted angiomas).

Cutaneous angiosarcoma of the buttock complicated by severe thrombocytopenia: A case report

Angiosarcoma (AS) is an aggressive, malignant endothelial cell tumor of vascular or lymphatic origin, the presentation and clinical behavior of which may vary according to its location. This is the case report of a 56-year-old woman with cutaneous angiosarcoma (CAS) of the buttock complicated by severe thrombocytopenia. A review of the literature revealed that only nine cases of CAS with thrombocytopenia have been previously reported. The prognosis of CAS complicated by thrombocytopenia is poor, even after treatment with combined chemotherapy and radiotherapy (RT). The composite karyotype was 46,XX,t(12;20)(p13;p11.2)[3]/47,X,add(X)(q13),del(6)(q?),add(12)(p13),−21,+2mar[2]/45,XX,der(1)add(1)(p36.3)del(1)(q41),−20[1]/46,XX[13]. Only 13 cytogenetic cases of AS, including the present case, have been reported in the English literature thus far. In this case report, the clinical presentation and cytogenetic findings are described and the relevant literature on AS is reviewed.

Pancreatic kaposiform hemangioendothelioma presenting with duodenal obstruction and kasabach-merritt phenomenon: a neonate cured by whipple operation

Aim Kaposiform hemangiondothelioma (KHE) is a rare vascular tumor, commonly associated with Kasaback–Merritt phenomenon characterized by thrombocytopenia and consumptive coagulopathy. We report a case of pancreatic KHE presenting with neonatal duodenal obstruction and Kasaback–Merritt phenomenon.

Case Report A full term male baby presented with bile stained vomiting on Day 3 of life. Contrast study and computed tomography scan showed duodenal obstruction by a 5 cm extrinsic hypervascular mass. Platelet count was 23 x 109/L. Laparotomy confirmed a vascular tumor arising from the pancreatic head compressing on the duodenum. Whipple operation was performed.

Results Intestinal obstruction and thrombocytopenia resolved after surgery. There was no post-operative complications. Histology confirmed KHE. The boy was tolerating hydrolyzed milk formula and was thriving at 5 months follow up.

Conclusion We reported a case of pancreatic KHE presented with neonatal intestinal obstruction and Kasaback–Merritt phenomenon. High index of suspicion is necessary for diagnosis. To our knowledge, this is the youngest patient who underwent Whipple operation.

Kasabach-Merritt syndrome in a child with upper airway compromise and spontaneous periorbital bruising

A hemangioma that rapidly increases in size has the potential to trap platelets and cause a consumptive coagulopathy. We describe the case of an 18-week-old boy who was brought to a local emergency department with ecchymosis on his nasal bridge and medial epicanthi, as well as a subconjunctival hemorrhage. He was noted to be anemic and thrombocytopenic. Packed red blood cells and platelets were transfused. However, despite hematologic correction, the ecchymosis and petechiae worsened, and a mass became evident in the right posterior triangle of the patient's neck. Computed tomography demonstrated a lobular soft-tissue-density mass in the right posterior triangle that extended to the level of the skull base. Histologic analysis of a biopsy specimen revealed that the lesion was a giant kaposiform hemangioma. The patient was diagnosed with Kasabach-Merritt syndrome, and prednisolone was commenced as a first-line treatment. However, the mass continued to grow, resulting in inspiratory stridor. Magnetic resonance imaging revealed encroachment into the thecal sac and compression of the spinal cord. The lesion was embolized, and vincristine therapy was commenced. Following a second embolization, the size of the lesion decreased and no further blood products were required. The hemangioma was deemed to be unresectable. The successful treatment in this case was dependent on the maintenance of hemostasis, the initial medical treatment with a corticosteroid, repeat embolization, and longer-term control with vincristine.

Hand-assisted laparoscopic splenectomy for a huge splenic vascular lesion with aneurysms in a patient with impending Kasabach-Merritt syndrome-like phenomenon

Splenic vascular lesions are relatively rare and are usually found incidentally. However, the vascular lesions associated with Kasabach-Merritt syndrome, such as hemangioma, can be life-threatening. We herein describe the case of a young adult female patient with a huge splenic vascular lesion, aneurysms of the splenic artery, and increased plasma levels of fibrin/fibrinogen degradation products and D-dimers. Hand-assisted laparoscopic splenectomy was performed, after which the coagulopathy was drastically improved. Minimally invasive surgical intervention such as hand-assisted laparoscopic splenectomy should be considered as the first treatment choice in such a case.

Medical management of tumors associated with Kasabach-Merritt phenomenon: an expert survey

Kasabach-Merritt phenomenon (KMP) is a rare consumptive coagulopathy characterized by profound thrombocytopenia and hypofibrinogenemia occurring in association with the vascular tumors kaposiform hemangioendothelioma (KHE) and tufted angioma (TA). Treatment remains challenging without consensus on the optimal medical management. The authors compiled expert opinions regarding management to establish treatment recommendations. Twenty-seven vascular anomalies centers in the United States and Canada were surveyed using 2 representative cases of KHE/TA with and without KMP. Overall response rate was 92% (25/27) with 88% completion (24/27). Most sites (23/25; 92%) do not have a standard of practice for management. The most frequent initial therapy for KHE+KMP was a combination of systemic corticosteroids and vincristine (VCR) (12/24 centers; 50%) followed by corticosteroids alone (29%). Second-line treatments were VCR (38%), rapamycin (21%), and propranolol (21%). Management of KHE/TA without KMP was variable; initial treatments included systemic corticosteroids (8/24; 33%) alone or with VCR (9/24; 38%), monitoring without medication (33%), VCR (8%), propranolol (8%), aspirin (4%), and rapamycin (4%). This survey highlights certain trends in the management of KMP-associated tumors, without standard protocols and consensus.

Kasabach-Merritt phenomenon: a report of 11 cases from a single institution

BACKGROUND

Kasabach-Merritt phenomenon (KMP) is a rare condition and optimal treatments have not yet been established, especially for cases that are unresponsive to first-line therapy. We retrospectively reviewed 11 KMP cases treated over the past 13 years in our institute.

OBSERVATIONS

With the exception of 1 case, steroids were administered as the first-line therapy. Eight cases required second-line or third-line therapy. The effective salvage therapies include interferon (n=1), radiotherapy (n=1), and chemotherapy (n=5). One case continues to depend upon chemotherapy. Three refractory cases were therapy dependent over 1 year of age, whereas 8 were treated effectively by 6 months of age.

CONCLUSIONS

Chemotherapy seems to be the most effective therapy for steroid-resistant KMP cases.

Angiosarcoma associated with a Kasabach-Merritt syndrome: report of two cases treated with paclitaxel

Angiosarcomas are rare, aggressive vascular malignancies of endothelial cell differentiation. Kasabach-Merritt syndrome is a rare condition defined by the association of thrombocytopenia and consumption coagulopathy with specific vascular tumors, such as tufted angioma or kaposiform hemangioendothelioma. We report here two cases of angiosarcomas complicated by a Kasabach-Merritt syndrome and their outcome after treatment with paclitaxel.

Anaesthetic management of a neonate with Kasabach-Merritt syndrome

Kasabach-Merritt syndrome is characterised by giant haemangioma, thrombocytopenia and coagulopathy. Triggering of disseminated intravascular coagulation along with the need for massive blood transfusion is the major intraoperative complication. A 1-month-old boy was scheduled for excision and split skin grafting of a giant haemangioma over the left thigh. Investigations revealed severe anaemia with thrombocytopenia that was uncorrected despite multiple blood transfusions. Other treatment modalities were also unsuccessful and the neonate was taken up for excision of the haemangioma in order to correct the consumptive coagulopathy. Standard anaesthesia was administered and all appropriate measures to reduce blood loss were instituted. Massive blood transfusion was required but the intraoperative and post-operative period was uneventful and followed by a significant improvement in the haemoglobin and platelet counts in the post-operative period.

Intratesticular kaposiform haemangioendothelioma in adults: a report of two cases

Kaposiform haemangioendothelioma is a very rare vascular tumour of intermediate (borderline) malignancy, typically occurring in the skin and soft tissues of the extremities in infants and children. We report two morphologically and immunophenotypically classical cases occurring in the testicular parenchyma of old adults, review the literature on vascular tumours of the testis and discuss the differential diagnosis of these unusual cases.

[Kaposiform haemangioendothelioma associated with B-cell acute lymphoblastic leukemia]

BACKGROUND

Herein, we report the first case of kaposiform haemangioendothelioma (KHE) associated with acute B-lymphoblastic leukemia (B-ALL).

PATIENTS AND METHODS

A five-month-old infant presented a plaque of angiomatous appearance on the forearm that had increased in volume since birth, as well as pallor and cutaneous haematomas. Kasabach-Merritt syndrome (KMS) was evoked despite hepatomegaly and considerable splenomegaly. Laboratory tests revealed severe anaemia and thrombocytopenia as well as major hyperleukocytosis with 90% blasts. Skin biopsy revealed vast vascular lobules containing cohesive fusiform endothelial cells not expressing Glut1, bound up in a dense infiltrate of B-lymphoblast cells. It was in fact KHE associated with B-ALL confirmed by the myelogram. The child was treated with the INTERFANT 2006 protocol followed by allograft of haematopoietic stem cells, which resulted in complete haematological remission. At the same time, almost total regression of KHE was noted.

DISCUSSION

In this infant, KHE had an inflammatory appearance and was associated with thrombocytopenia, evocative of KMS. Analysis of blood and marrow samples resulted in a diagnosis of B-ALL. Histopathological examination of the angioma revealed a typical appearance of KHE associated with dense lymphoblastic proliferation. This appearance could have resulted either from passive contamination by circulating blast cells or from active recruitment of tumor cells at the KHE site.

CONCLUSION

HK mimicking KMS may reveal B-ALL.

Successful treatment of Kasabach-Merritt syndrome with transarterial embolization and corticosteroids

Kasabach-Merritt syndrome (KMS) refers to the combination of large neonatal vascular tumors and thrombocytopenic coagulopathy. However, a standard treatment regimen for KMS has not yet been established. We report a case of a 6-week-old male infant with life-threatening KMS who was successfully treated with transarterial embolization and corticosteroids. One week after initiating the corticosteroid treatment, his platelet counts recovered, and the lesion growth halted. The approach with corticosteroid therapy resulted in an excellent response that was maintained long enough for us to perform transarterial embolization therapy. The combination of transarterial embolization and corticosteroid therapy should be considered as an option for Kasabach-Merritt syndrome.

Kaposiform hemangioendothelioma: atypical features and risks of Kasabach-Merritt phenomenon in 107 referrals

OBJECTIVE

To examine the presentation characteristics of patients with Kaposiform hemangioendothelioma (KHE) to describe the spectrum of disease and risk factors for Kasabach-Merritt phenomenon (KMP).

STUDY DESIGN

A retrospective review of 163 patients referred to the Vascular Anomalies Center at Children's Hospital Boston for KHE between 1991 and 2009 identified 107 patients with sufficient data for inclusion.

RESULTS

The prevalence of KHE in Massachusetts is ∼0.91 case per 100000 children. KHE manifested in infancy in 93% of cases, with 60% as neonates. Common presenting features included enlarging cutaneous lesion (75%), thrombocytopenia (56%), and musculoskeletal pain or decreased function (23%). Cutaneous KHE favored the extremities, especially overlying joints. In our cohort, 71% developed KMP (11% after initial presentation), and 11% of patients lacked cutaneous findings. Retroperitoneal and intrathoracic lesions, though less common, were complicated by KMP in 85% and 100% of cases, respectively. Compared with superficial lesions, KHE infiltrating into muscle or deeper was 6.3-fold more likely to manifest KMP and 18-fold higher if retroperitoneal or intrathoracic. KHE limited to bone or presenting after infancy did not manifest KMP.

CONCLUSION

An enlarging cutaneous lesion is the most common presenting feature of KHE in infancy. Older patients with KHE or those lacking cutaneous manifestations present with musculoskeletal complaints or atypical symptoms. The risk of KMP increases dramatically when tumor infiltrates muscle or when KHE arises in the retroperitoneum or mediastinum.

Myometrial cavernous hemangioma with pulmonary thromboembolism in a post-partum woman: a case report and review of the literature

Introduction

Cavernous hemangiomas of the uterus are rare benign vascular lesions. Nine cases of diffuse cavernous hemangioma of the gravid uterus have been reported, most of which diffusely involved the myometrium. These vascular malformations are clinically significant, and may cause pronounced bleeding resulting in maternal or fetal demise. Thrombosis of cavernous hemangiomas of the uterus has been previously reported. We here report the first case in which a thrombosed cavernous hemangioma of the myometrium resulted in a fatal pulmonary embolism in a post-partum woman.

Case presentation

A 25-year-old obese African-American woman who had one pregnancy and was delivered of twins by cesarean section was admitted 1 week after the successful delivery. The 12-day clinical course included ventilator-dependent respiratory failure, systemic hypertension, methicillin-resistant Staphylococcus aureus in the sputum, leukocytosis and asystole. A transabdominal ultrasound examination showed heterogeneous thickened and irregular products in the endometrial canal. The laboratory values were relevant for an increased prothrombin time, activated partial thromboplastin time, ferritin and a decrease in hemoglobin. The clinical cause of death was cited as acute respiratory distress syndrome. At autopsy, a 400g spongy, hemorrhagic uterus with multiple cystic spaces measuring approximately 0.5 × 0.4cm filled with thrombi within the myometrium was identified. Immunohistological examination with a CD31 stain for vascular endothelium associated antigen confirmed several endothelium-lined vessels, some of which contained thrombi. These histological features were consistent with cavernous hemangioma of the myometrium. A histological examination of the lungs revealed multiple fresh thromboemboli in small- and medium-sized pulmonary arteries in the right upper and lower lobes without organization, but with adjacent areas of fresh hemorrhagic infarction.

Conclusion

This case underscores the importance of a high index of suspicion in a pregnant or post-partum woman presenting with respiratory symptoms. Thrombosis of the cavernous hemangiomas of the gravid or post-partum uterus is a rare entity. This case is of interest because it indicates that this condition can be fatally complicated by embolization of the thrombi in the cavernous myometrial hemangiomas. Although delivery by conservative methods, as well as cesarean section, is possible without resorting to hysterectomy, occasionally, the consequences could be fatal as in this case.

Neonatal Kasabach-Merritt phenomenon

Kasabach-Merritt phenomenon (KMP) is a life-threatening consumptive coagulopathy in the presence of a rapidly enlarging vascular tumor. It usually presents in early infancy, but onset in early neonatal period, facial hemangioma, and vincristine use in neonates has rarely been reported. We, hereby, present a 6-day-old male child presenting with facial hemangioma and intracranial hemorrhage, and KMP responding well to steroids and vincristine. Pathophysiology of disease and various treatment options have been discussed.

GI-Associated Hemangiomas and Vascular Malformations

Hemangiomas and vascular malformations of the gastrointestinal tract, rare clinical entities, present as overt or occult bleeding. They can be distributed throughout the intestinal digestive system, or present as a singular cavernous hemangioma or malformation, which is often located in the rectosigmoid region. Misdiagnosis is common despite characteristic radiographic features such as radiolucent phleboliths on plain film imaging and a purplish nodule on endoscopy. Adjunctive imaging such as computed tomography and magnetic resonance imaging are suggested as there is potential for local invasion. Endorectal ultrasound with Doppler has also been found to be useful in some instances. Surgical resection is the mainstay of treatment, with an emphasis on sphincter preservation. Nonsurgical endoscopic treatment with banding and sclerotherapy has been reported with success, especially in instances where an extensive resection is not feasible.

Laparoscopic resection of a giant exophytic liver haemangioma with the laparoscopic Habib 4× radiofrequency device

Haemangiomas are the most common solitary benign neoplasm of the liver with an incidence ranging from 5% to 20%. Although usually small and asymptomatic, they may reach considerable proportions and rarely give rise to life-threatening complications. Surgical intervention is required for incapacitating symptoms, established complications, and diagnostic uncertainty. The resection of haemangiomas demands meticulous surgical technique, owing to their high vascularity and the concomitant risk of intra-operative haemorrhage. Laparoscopic resection of giant haemangiomas is even more challenging, and has only been reported twice. We here report the case of a giant 10 cm liver haemangioma which was successfully resected laparoscopically using the laparoscopic HabibTM 4×, a bipolar radiofrequency device, without clamping major vessels and with minimal blood loss. Transfusion of blood or blood products was not required. The patient had an uneventful recovery and was asymptomatic at 7-mo follow-up.

Thrombotic microangiopathies

Thrombotic microangiopathy results from thrombotic occlusion of the microvasculature leading to fragmentation of red blood cells, profound thrombocytopenia, and a microangiopathic hemolytic anemia with elevation of lactate dehydrogenase and negative direct Coomb's test. This constellation of clinical and laboratory findings is not due to one disease entity; rather, it represents a variety of underlying diagnoses. Among the major disease entities are TTP/HUS, which can be congenital or acquired, bacterial infections, medications, vascular or endothelial pathology like Kasabach-Merritt phenomenon, and stem cell transplantation. In this paper, we offer a review of some of the major causes of thrombotic microangiopathy.

Diagnosis and management of neonatal thrombocytopenia

Thrombocytopenia is the most common haematological abnormality in newborns admitted to neonatal care units and serves as an important indicator of underlying pathological processes of mother or child. In most cases thrombocytopenia is mild to moderate and resolves within the first weeks of life without any intervention. However, in some neonates thrombocytopenia is severe or may reflect an inborn platelet disorder. As clinical course and outcome of thrombocytopenia depend on the aetiology of thrombocytopenia, an appropriate work-up is essential to guide therapy in neonates with thrombocytopenia and to avoid severe bleeding.

Calcified subgaleal hematoma with secondary cranial deformity in a patient with Kasabach-Merritt phenomenon

We present here the case of a 25-month-old boy who, in conjunction with his preexisting Kasabach-Merritt phenomenon (KMP), developed a massive calcified subgaleal hematoma (SGH) with secondary cranial deformity. Kasabach-Merritt phenomenon is a rare condition that involves a secondary consumptive coagulopathy in the setting of congenital hemangiomatous lesions. The vascular lesions of KMP are often large, singular, and cutaneous, but may also be diffuse, and involve internal structures. Subgaleal hematomas are a rare condition, most frequently observed in neonates as a complication of instrument-assisted delivery. There have been few cases reported beyond the perinatal period, but those that are present within the literature have typically resulted from some instance of minor trauma to the scalp. Most cases resolve spontaneously and without complication. However, our patient's SGH developed into a large, organized, and calcified lesion, likely with some contribution from his hematologic deficit. In addition, this subgaleal lesion resulted in a cranial deformity, ultimately requiring surgical evacuation and reconstruction. We believe the case presented here represents the first report of an SGH in the setting of KMP.

Bleeding disorders in neonates

SUMMARY

Bleeding disorders may present during the neonatal period, however, absent patient history along with unique physical signs, physiologically decreased levels of plasma proteins and laboratory variations of platelet function tests may render any diagnosis difficult to establish. Intra cranial haemorrhage (ICH) may be the clinical presenting symptom of a severe coagulation factor deficiency. Haemophilia in the newborn period poses unique challenges in diagnosis and management, Data presented from the UDC and similar surveillance systems world-wide can be used to further clinical research and improve management strategies. Development haemostasis should be considered as well as laboratory variations of coagulation tests while evaluating and diagnosis neonates suspected of bleeding disorders. Therapy of bleeding episodes in the neonate relies upon proper replacement and repeated haemostatic evaluation of patients' status, while dealing with underlying etiological causes. This manuscript discusses the unique aspects of clinical presentation, laboratory assessment, and treatment of various bleeding disorders in neonates.

Kasabach merritt syndrome: management with interferon

Kasabach Merritt Syndrome (KMS) is a rare, locally aggressive, vascular tumor. The objectives of treatment of KMS are to prevent bleeding from consumptive coagulopathy and induce vascular tumor regression. A 14-month old female child was brought with a reddish lesion on the left scapular area noticed at birth, which suddenly increased in size since 3 days. Hemogram revealed anemia severe thrombocytopenia, prolongation of bleeding, clotting time and increased fibrin degradable products, suggestive of KMS. Coagulopathy was managed by transfusing fresh frozen plasma and platelets. Oral prednisolone up to 5mg/kg/day for four weeks yielded no effect on thrombocytopenia or regression of tumor size. Embolization of feeding artery was attempted but not feasible. We used Interferon –alpha– 2b (IFN α 2b), in a dosage of 3million IU/m² /day subcutaneously. Within a month the platelet count increased and the vascular tumor started regressing. This case signifies the importance of step wise management of KMS.

Kasabach-merritt syndrome arising from tufted angioma successfully treated with systemic corticosteroid

We report a case of Kasabach-Merritt syndrome arising from a tufted angioma successfully treated with systemic corticosteroid. A 2-month-old male infant presented with a palm-sized, erythematous induration on his left pubis. The lesion was diagnosed as tufted angioma histopathologically. After 1 month, the lesion suddenly expanded to the abdomen and scrotum. Initial laboratory tests were consistent with consumptive coagulopathy. He was diagnosed with Kasabach-Merritt syndrome and treated with intravenous dexamethasone at 0.32 mg/kg/day (equivalent to prednisolone 2.0 mg/kg/day). Two days after initiating the treatment, his platelet counts recovered and the lesion ceased to expand. Steroid therapy was converted to oral prednisolone and the dosage was subsequently tapered, and the lesion gradually involuted with no signs of recurrence for a year.

Early human development: neonatal tumours: vascular tumours

Vascular tumours (haemangiomas and malformations) are common tumours of infancy and childhood. They represent a group of mostly benign conditions, which present early, can grow rapidly and be symptomatic or disfiguring. There are various management options, with different cosmetic and functional outcomes. Haemangiomas and vascular malformations have different clinical courses which dictate respective management; differentiating them is key. Haemangiomas are generally self-limiting after initial proliferation; generally management is conservative. Symptoms can call for treatment. Options include laser, steroids, chemotherapy and surgery. Propanolol, the newest modality of treatment, may have a dramatic effect in problematic lesions. Vascular malformations are a less common group of heterogenous lesions, with some overlap between entities. They do not involute. Treatment options include laser therapy, sclerotherapy, embolisation, and surgery. Emerging therapies include photodynamic therapy and angiogenesis inhibitors. This review will outline the evidence for the various modalities in managing these conditions.

Kasabach-Merritt phenomenon

The objective of this article is to provide a comprehensive overview of the Kasabach-Merritt Phenomenon. The clinical presentation, laboratory findings, vascular pathology, and pathophysiology are discussed.

Hemangiomas of the pelvis

Hemangiomas of the colon and rectum are rare but often misdiagnosed causes of hematochezia. They are characterized by the clinical triad of recurrent episodes of painless rectal bleeding, multiple ectopic phleboliths on plain radiographs, and cutaneous hemangiomas. The majority of these tumors involve the rectosigmoid region. Diffuse cavernous lesions are the most common histological type. Endoscopy is important to define the extent and number of lesions. Imaging by computed tomography or magnetic resonance imaging is used to define invasion into pelvic structures. Surgical resection with preservation of the sphincters is the recommended treatment.

Diagnosis and management of bleeding disorder in a child

Children with symptoms of bleeding and bruising are commonly seen in clinical practice. Primary care providers should be able to decide when and whether evaluation for bleeding disorder is warranted. This decision depends on one's index of suspicion for bleeding disorder based on history, physical examination, and screening laboratory investigations. Knowledge of the hemostatic physiology is essential to be able to order appropriate laboratory investigations and their accurate interpretation. Prothrombin time (PT), activated partial thromboplastin time (aPTT), and blood platelet concentration constitute the initial diagnostic work up of any bleeding disorder. Abnormality in any of these parameters in a child with excessive bleeding should lead to presumptive diagnosis of bleeding disorder and trigger referral to a hematologist for confirmation and definitive treatment. Awareness of basic treatment principles for management of bleeding/clotting disorders may prepare the provider to develop appropriate management plans, especially in a life threatening situation.

Coagulopathy in critically ill patients: part 1: platelet disorders

Abnormalities of platelet number and function are the most common coagulation disorders seen among ICU patients. This article reviews the most frequent causes of thrombocytopenia by providing an overview of the following most common mechanisms: impaired production; sequestration; dilution; and destruction. Guidelines for treating thrombocytopenia and platelet dysfunction are also provided.

Kasabach-Merritt phenomenon: a single centre experience

OBJECTIVE

Kasabach-Merritt phenomenon (KMP) can lead to life-threatening bleeding, and its optimum treatment has not been established. We review the experience of managing KMP in a single institution.

METHODS

A retrospective chart review on all children with KMP treated at the Hospital for Sick Children, Toronto, over an 18 yr period was carried out.

RESULTS

All 15 patients had profound thrombocytopenia and hypofibrinogenemia at presentation, half had bleeding symptoms, and three had cardiac failure. All patients received corticosteroids. Five responded to steroids alone, given for an average of 13 wk, increasing platelets to >20 x 10(9)/L at a mean of 6.2 d and fibrinogen >1 g/dL at 25.6 d. Ten patients received at least one other therapeutic modality in addition to steroids, including vincristine, interferon, anti-platelet agents and pentoxifylline. Five patients received vincristine, for a mean of 6 wk, with two patients responding. Eight patients received interferon, for a mean of 4 months, with two patients responding. Overall, the mean time to increasing platelets >20 x 10(9)/L was 56 d, to >150 x 10(9)/L was 88 d and fibrinogen >1 g/dL 49 d. Ten patients showed a partial response to embolisation, with a mean of 2.8 procedures performed. Thrombotic complications occurred in 7%. Twelve patients remain alive, with relapse in six patients, all treated successfully. One patient died, and two patients have been lost to follow-up.

CONCLUSION

KMP is a rare condition, with significant morbidity and mortality. The therapeutic approach should include a multidisciplinary team and consensus on guidelines.

Kaposiform hemangioendothelioma (with Kasabach Merritt syndrome) of the head and neck: case report and review of the literature

An infant initially diagnosed with a parotid hemangioma presented with stridor and thrombocytopenia. Diagnosis of Kaposiform hemangioendothelioma was confirmed with biopsy. The child succumbed to multi-system organ failure related to consumptive coagulopathy despite aggressive medical management. Kaposiform hemangioendothelioma is a rare head and neck tumor that may be mistaken for a hemangioma on preliminary diagnosis, which may lead to increased morbidity and mortality especially in the setting of Kasabach-Merritt phenomenon. A platelet count may provide an early and important clue to the possibility of coagulopathy; prompting physicians to look for a diagnosis other than a simple hemangioma.