Successful treatment of pediatric histiocytic sarcoma using abbreviated high-risk leukemia chemotherapy.

Histiocytic sarcoma (HS) is a malignant tumor composed of proliferating cells of histiocytic origin. True HS is exceedingly rare, particularly in pediatric patients. These tumors are frequently aggressive, and outcome for patients with HS has traditionally been poor. There is currently no consensus on the optimal management of these tumors, with the literature consisting largely of case reports and small case series utilizing a wide variety of therapies. We describe a case of HS in an 8-year-old female who was successfully treated with an abbreviated leukemia chemotherapy regimen.

Comparison of conventional and simulated reduced-tube current MDCT for evaluation of suspected appendicitis in the pediatric population.

OBJECTIVE: The purpose of this study was to compare CT with conventional and simulated reduced-tube current in the evaluation for acute appendicitis in children. MATERIALS AND METHODS: Validated noise-addition (tube current-reduction) software was used to create 50% and 75% tube current reductions in 60 CT examinations performed for suspected appendicitis, resulting in 180 image sets. Three blinded pediatric radiologists scored the randomized studies for the following factors: presence of the normal appendix or appendicitis (5-point scale; 1=definitely absent and 5=definitely present), presence of alternate diagnoses, and overall image quality (1=nondiagnostic and 5=excellent). Truth was defined by the interpretation of the conventional examination. RESULTS: For conventional examinations, the total number of reviews (60 cases×3 readers=180) in which the normal appendix was identified was 120 of 180 (66.7%), compared with 108 of 180 (60%) in the 50% (p=0.19) and 91 of 180 (50.6%) in the 75% (p=0.002) tube current-reduction groups. Appendicitis was identified in a total of 39 of 180 (21.7%), 38 of 180 (21.1%), and 37 of 180 (20.6%) examinations, respectively (p>0.05). This translates to sensitivities of 97% and 95% for the 50% and 75% tube current-reduction groups, respectively. Alternate diagnoses were detected in 14%, 16%, and 13% of scans, respectively. Compared with conventional-tube current examinations, reader confidence and assessment of image quality were significantly decreased for both tube current-reduction groups. CONCLUSION: Simulated tube current-reduction technology provides for systematic evaluation of diagnostic thresholds. Application of this technology in the setting of suspected appendicitis shows that tube current can be reduced by at least 50% without significantly affecting diagnostic quality, despite a decrease in reader confidence and assessment of image quality.

MLL duplication in a pediatric patient with B-cell lymphoblastic lymphoma.

Lymphoblastic lymphoma is the second most common type of non-Hodgkin lymphoma seen in children. Approximately, 90% of lymphoblastic lymphomas arise from T cells, with the remaining 10% being B-cell-lineage derived. Although T-cell lymphoblastic lymphoma most frequently occurs in the anterior mediastinum (thymus), B-cell lymphoblastic lymphoma (B-LBL) predominates in extranodal sites such as skin and bone. Here, we describe a pediatric B-LBL patient who presented with extensive abdominal involvement and whose lymphoma cells displayed segmental duplication of the mixed lineage leukemia (MLL) gene. MLL duplication/amplification has been described primarily in acute myeloid leukemia and myelodysplastic syndrome with no published reports of discrete MLL duplication/amplification events in B-LBL. The MLL gene duplication noted in this case may represent a novel mechanism for tumorigenesis in B-LBL.

A young patient with polyarthralgia and hearing loss: a case report of Muenke syndrome.

There are few reports of the typical radiographic findings in the hands and feet of patients with Muenke syndrome. We present a case report of a young girl with Muenke syndrome, whose diagnosis was made following the observation of coalitions and coned epiphyses on hand radiographs.

Enhancing pediatric safety: assessing and improving resident competency in life-threatening events with a computer-based interactive resuscitation tool.

BACKGROUND: Though rare, allergic reactions occur as a result of administration of low osmolality nonionic iodinated contrast material to pediatric patients. Currently available resuscitation aids are inadequate in guiding radiologists' initial management of such reactions. OBJECTIVE: To compare radiology resident competency with and without a computer-based interactive resuscitation tool in the management of life-threatening events in pediatric patients. MATERIALS AND METHODS: The study was approved by the IRB. Radiology residents (n = 19; 14 male, 5 female; 19 certified in basic life support/advanced cardiac life support; 1 certified in pediatric advanced life support) were videotaped during two simulated 5-min anaphylaxis scenarios involving 18-month-old and 8-year-old mannequins (order randomized). No advance warning was given. In half of the scenarios, a computer-based interactive resuscitation tool with a response-driven decision tree was available to residents (order randomized). Competency measures included: calling a code, administering oxygen and epinephrine, and correctly dosing epinephrine. RESULTS: Residents performed significantly more essential interventions with the computer-based resuscitation tool than without (72/76 vs. 49/76, P < 0.001). Significantly more residents appropriately dosed epinephrine with the tool than without (17/19 vs. 1/19; P < 0.001). More residents called a code with the tool than without (17/19 vs. 14/19; P = 0.08). A learning effect was present: average times to call a code, request oxygen, and administer epinephrine were shorter in the second scenario (129 vs. 93 s, P = 0.24; 52 vs. 30 s, P < 0.001; 152 vs. 82 s, P = 0.025, respectively). All the trainees found the resuscitation tool helpful and potentially useful in a true pediatric emergency. CONCLUSION: A computer-based interactive resuscitation tool significantly improved resident performance in managing pediatric emergencies in the radiology department.

Radiologists' agreement when using a 10-point scale to report abdominal radiographic findings of necrotizing enterocolitis in neonates and infants.

OBJECTIVE: The purpose of this study was to evaluate radiologists' agreement when using a 10-point scale of abnormal findings designed to standardize reporting of abdominal radiographs in neonates or infants with suspected necrotizing enterocolitis. MATERIALS AND METHODS: A 10-point scale of radiographic findings was devised at our institution and was in use for approximately 18 months before the initiation of this study. After institutional review board approval, 88 abdominal radiographs (anteroposterior and cross-table lateral) were randomly selected for review, allowing for an equal distribution of examinations throughout the scale according to the original examination report. The mean age of the patients in the total study population was 24.9 days (range, 0-56 days); 61 patients (47.3%) were girls and 68 (52.7%) were boys. Four pediatric radiologists having 20, 13, 7, and 5 years of experience scored images twice at least 4 weeks apart according to the scale, which was designed to characterize certainty and severity of disease in neonates and infants with possible necrotizing enterocolitis. Interobserver and intraobserver agreement was assessed by applying weighted kappa statistics. Operative and pathology reports were reviewed. RESULTS: The average intraobserver weighted kappa value was 0.792 (SD, 0.025; range, 0.635-0.946). The average interobserver weighted kappa value was 0.665 (SD, 0.035, range, 0.574-0.898). CONCLUSION: Substantial intraobserver and interobserver agreement was found when radiologists used a 10-point scale to report abnormal findings on abdominal radiographs in neonates or infants with suspected necrotizing enterocolitis. This scale warrants further evaluation as a potentially useful clinical tool.