In the Literature: HM-Related Research You Need to Know

In the validation sample, 10.6% of patients had HN and 3.3% had HNRI. The negative predictive value for HN was 96.9%, sensitivity 91.8%, and negative likelihood ratio 0.27. The number needed to screen (NNS) low-risk patients for HN was 32 and 223 for HNRI. Based on their findings, if the patient was classified low-risk, clinicians might be able to delay or avoid ordering RUS.

The major limitation of this study was that it was based at a single institution. This study only evaluated RUS obtained in patients who were hospitalized and might not be applicable to outpatients.

Bottom line: RUS was not found to change clinical management in patients with AKI and classified as low-risk for HN. Limiting RUS to patients who are high-risk for obstruction will increase the chance of finding useful clinical information that can change management decisions and limit cost of unnecessary testing.

Citation: Licurse A, Kim MC, Dziura J, et al. Renal ultrasonography in the evaluation of acute kidney injury: developing a risk stratification framework. Arch Intern Med. 2010;170(21):1900-1907.

Romiplostim Has Higher Rate of Platelet Response and Fewer Adverse Events in Patients with Immune Thrombocytopenia

Clinical question: Does the use of romiplostim lead to increased platelet counts and lower rates of splenectomy and other adverse events when compared with standard therapy in patients with immune thrombocytopenia?

Background: Romiplostim is a thrombopoetin mimetic used to increase platelet counts in immune thrombocytopenia. Initial treatments for this disease involve glucocorticoids or intravenous immune globulin. Most patients require second-line medical or surgical therapies, including splenectomy.

Study design: Randomized, open-label controlled trial.

Setting: Eighty-five medical centers in North America, Europe, and Australia.

Synopsis: A total of 234 patients were randomized in a 2:1 ratio to receive either romiplostim or the medical standard of care. Co-primary endpoints were the incidence of treatment failure and the incidence of splenectomy; secondary endpoints included time to splenectomy, platelet count, platelet response, and quality of life. Treatment failure was defined as a platelet count of 20x109 per liter or lower for four weeks, or a major bleeding event.

At the end of 52 weeks, patients receiving romiplostim had higher platelet counts, fewer bleeding events, less need for splenectomy (9% vs. 36%), and a better quality of life.

The short-term use of romiplostim in this study was not associated with an increase in adverse events when compared with standard therapy. However, maintenance of the elevated platelet count, which results from romiplostim treatment, requires continuous use of the drug; the long-term effects are unknown.

Bottom line: In patients with immune thrombocytopenia, romiplostim leads to increased platelet counts, decreased bleeding events, and decreased need for splenectomy compared to standard of care. However, the cost of the medication, when compared with current therapies, could be prohibitive.

Citation: Kuter DJ, Rummel M, Boccia R, et al. Romiplostim or standard of care in patients with immune thrombocytopenia. N Engl J Med. 2010;363(20):1889-1899. TH

Pediatric HM Literature

Parental History Portends Persistent Chronic Abdominal Pain in Children

Reviewed by Pediatric Editor Mark Shen, MD, medical director of hospital medicine at Dell Children’s Medical Center, Austin, Texas.

Clinical question: What is the quality of the current evidence for potential prognostic factors of persistent chronic abdominal pain in children?

Background: Chronic abdominal pain (CAP) is a prevalent condition in childhood that might be associated with increased healthcare costs, including hospital admission. Retrospective studies have implicated psychosocial factors as being of prognostic relevance, but these are unable to offer greater insight into the relationship given the complex nature of this chronic illness.

Study design: Systematic review of literature.

Setting: MEDLINE, EMBASE, and PsycINFO.

Synopsis: The databases were searched through June 2008 for articles that focused on children 4 to 18 years of age; used criteria for CAP as defined by Apley and Naish, von Baeyer and Walker, or the Rome Committee; and demonstrated prospective determination of outcomes. Eight studies were included in the final review, and the levels of evidence were graded based on assessment of risk for bias.

Female sex and severity of baseline abdominal pain did not predict persistence of CAP, although there was conflicting evidence as to the role of psychological factors. There was moderate evidence that having a parent with functional gastrointestinal (GI) symptoms predicted persistence of CAP in children, and there was weak evidence that having parents who eschew psychological factors in favor of searching for an organic explanation predicted persistence of CAP.

Due to a limited number of studies or conflicting associations, conclusions regarding the following factors could not be drawn: age, educational level, duration of CAP, associated symptoms, socioeconomic status, and history of two or more surgical operations.

In addition, the univariate analysis used by the included studies might not be appropriate for such a multifactorially complex disease. Nevertheless, this study challenges the conventional wisdom that psychological factors predict persistence of pain and should remind clinicians to assess for parental functional GI disorders in this patient population.

Bottom line: Parental history of functional GI disorders predicts persistence of CAP in children.

Citation: Gieteling MJ, Bierma-Zeinstra SM, van Leeuwen Y, Passchier J, Berger MY. Prognostic factors for persistence of chronic abdominal pain in children. J Pediatr Gastroenterol Nutr. 2011;52(2):154-161.