Home treatment of mild to moderate bleeding episodes using recombinant factor VIIa (Novoseven) in haemophiliacs with inhibitors.

OBJECTIVE: To assess the safety and efficacy of a fixed dose of recombinant activated factor VII (rFVIIa; NovoSeven) in the home setting for mild to moderately severe joint, muscle; and mucocutaneous bleeding episodes in patients with haemophilia A or B with inhibitors. DESIGN: Multicentre, open-label, single arm, phase III study of one year duration. METHODS; Patients or their caregivers administered up to three doses of rFVIIa (90 microg/kg i.v.) at 3 h intervals within 8 h of the onset of a mild to moderate bleeding episode. Once the subject considered that rFVIIa had been "effective" with regard to haemostasis (after 1-3 injections), one further (maintenance) dose of rFVIIa was administered. RESULTS: Of 60 patients enrolled, 56 experienced at least one bleed, and 46 completed the one year study. 614 of 877 bleeds (70%) were evaluable according to protocol definitions. Haemostasis was rated as "effective" in 92% (566/614) of evaluable bleeds after a mean of 2.2 injections. For successfully treated episodes, the time from onset of bleeding until administration of the first injection was 1.1+/-2.0 h (mean+/-SD). Twenty-four hours after initial successful response, haemostasis was reported as having been maintained in 95% of cases. Efficacy was comparable for muscle, joint and target joint, and mucocutaneous bleeding episodes. In an intent-to-treat analysis of all 877 bleeding events, efficacy outcomes were equivalent to the evaluable bleeds, with an effective response in 88% of treated episodes. Treatment-related adverse events occurred in 32 (3% of all) bleeding episodes and consisted of re-bleeds/new bleeds in more than 50% (18/32) of these events. A single episode of superficial thrombophlebitis was the only thrombotic complication encountered, and there were no patient withdrawals due to adverse events. Development of FVII(a) antibodies could not be detected, and hypersensitivity reactions to rFVIIa were not reported. CONCLUSION: rFVIIa is effective and well tolerated when used in the home setting to treat mild to moderate bleeding episodes in patients with haemophilia A or B with inhibitors.

Preoperative chemotherapy in the management of intracaval extension of Wilms' tumor.

Extension of Wilms' tumor into the renal vein and vena cava complicates the operative treatment of a small but significant number of patients. Two children presented with Wilms' tumor and intracaval tumor extension. After biopsy, both children were given chemotherapy. In one case the tumor completely disappeared from the vena cava, and in the other the tumor regressed substantially, and proximal control became possible at the level of the infrahepatic vena cava. Both children then had an uneventful nephrectomy that was greatly simplified. We conclude that preoperative chemotherapy can induce resolution of intravascular tumor, and may be a useful option in cases of extension of Wilms' tumor into the vena cava.

Intestinal necrosis from congenital hypercoagulopathy.

Protein-S deficiency is a rare congenital disorder that results in a hypercoagulable state, typically presenting as recurrent venous thrombosis in adults. Few cases have been reported in children. A 2-year-old girl presented in septic shock. During laparotomy, ischemic necrosis of the intestine was noted, which extended from the gastroesophageal junction to the midjejunum. Total gastrectomy, pancreaticoduodenectomy , and partial resection of the small intestine were performed. She was left with 140 cm of distal small bowel, and had reconstruction with a single limb for the pancreaticojejunostomy, choledochojejunostomy, and esophagojejunostomy to preserve intestinal length. Postoperative evaluation eventually disclosed a previously unrecognized protein-S deficiency. The hypercoagulopathy of protein-S deficiency can be complicated by catastrophic thrombotic events that require surgery. This congenital disorder should be considered in any child who has an unexplained thrombotic episode, because failure to recognize protein-S deficiency may have potentially fatal consequences.

The desmoplastic round cell tumor: a new solid tumor of childhood.

Three patients with a new, pathologically distinct solid tumor of childhood have been treated recently. The disease is characterized by male predominance, adolescent onset, an extensive abdominal primary tumor, and aggressive metastases to regional lymph nodes, liver, and lung. Two patients presented with vague abdominal pain and the third with testicular pain. All three noted fatigue and malaise of less than two months' duration with minimal associated weight loss. Computed tomography (CT) scans of the abdomen and chest were obtained for initial preoperative staging, and then all three underwent surgical exploration. Widespread disease was found in each case. In no instance was complete tumor extirpation possible because of extensive peritoneal spread and lymphatic and hepatic metastases. Histologically, all three tumors consisted of round blue cells with a dense desmoplastic reaction and focal rhabdoid features. Immunohistochemical markers for epithelial, neural, and muscle elements were positive. Aggressive multidrug chemotherapeutic regimens were used in each case, and all three patients are alive and well but with known residual disease. We conclude that in cases of the desmoplastic round cell tumor of childhood, CT scans underestimate the extent of disease, and exploratory laparotomy is necessary for diagnosis and appropriate staging. Surgery is usually palliative because of extensive spread. Awareness of this newly recognized aggressive solid tumor of childhood is essential to define its natural history and guide the development of effective multidisciplinary therapeutic regimens.

Inhibition of nucleoside transport by nitrobenzylthioformycin analogs.

The formycin analogs of nitrobenzylthioinosine and nitrobenzylthioguanosine were synthesized and evaluated as nucleoside transport inhibitors. These analogs have a potential therapeutic advantage over their parent compounds in that their C-nucleosidic linkages prevent them from being degraded to the immunosuppressive agents, 6-mercaptopurine and 6-thioguanine. 7-[(4-Nitrobenzyl)-thio]-3-(beta-D-ribofuranosyl)pyrazolo[4,3- d]pyrimidine (NBTF) and 5-amino-7-[(4-nitrobenzyl)thio]-3-(beta-D- ribofuranosyl)pyrazolo[4,3-d]pyrimidine (NBTGF) were inhibitors of nucleoside transport in human erythrocytes and HL-60 leukemia cells. The IC50 value for nitrobenzylthioinosine, NBTF and NBTGF with 10% erythrocyte suspensions were 18, 18 and 40 nM respectively. Specific binding studies with [3H]NBTF yielded a Kd of 3.4 nM with erythrocytes, approximately 10-fold higher than values reported for nitrobenzylthioinosine. NBTF and nitrobenzylthioinosine bound to HL-60 cells with Kd values of 8.1 and 0.81 nM respectively. The octanol/water partition coefficients of nitrobenzylthioinosine, NBTF and NBTGF were 3.5, 3.2, and 2.8 respectively. NBTF could be expected to be equipotent with nitrobenzylthioinosine in whole blood where inhibitor concentrations of 10(-7) to 10(-6) M are required in order to saturate erythrocytic binding sites; hence, it may exhibit the advantages inherent in a C-nucleoside.