Recurrent Atypical Hemolytic Uremic Syndrome in Children With Acute Lymphoblastic Leukemia Undergoing Maintenance Chemotherapy.

Chemotherapy-associated myelosuppression and renal dysfunction is not uncommon during childhood acute lymphoblastic leukemia (ALL) therapy. Here we report 2 cases of atypical hemolytic uremic syndrome (aHUS) presenting with pancytopenia and renal dysfunction that developed during maintenance chemotherapy characterized by hypocomplementemia. Both cases experienced recurrence after resolution of the initial aHUS episode upon resumption of chemotherapy, raising a possible contributory role for chemotherapy in the disease pathogenesis.

Invasive Pneumococcal Disease in Patients With Sickle Cell Disease.

BACKGROUND: Patients with sickle cell disease (SCD) are at risk of fatal sepsis with encapsulated bacteria, such as Streptococcus pneumoniae, because of the inherent autosplenectomy that occurs in SCD. This risk is thwarted with oral penicillin prophylaxis during the first 5 years of life, and with stringent vaccination against S. pneumoniae alongside routine childhood immunization. But compared with the general African American pediatric population, the rate of invasive pneumococcal disease (IPD) in patients with SCD still remains high, resulting in hospitalization and fatality. METHODS: Patients with SCD who developed IPD from 2004 up to 2013 were identified using microbiology records. Descriptive analysis of presence of risk factors for IPD, type of SCD, pneumococcal vaccination and prophylaxis status, clinical presentation, microbiological data, and the outcome of IPD was performed. RESULTS: Eight patients with SCD developed IPD (7 bacteremia and 1 respiratory tract infection). Three of the 8 isolates underwent serotype analysis (15 C in 2 and 15A in 1), none covered with the current vaccination program. One patient had fatal outcome (15A). CONCLUSIONS: Breakthrough cases of IPD may involve nonvaccine isolates, and seem to occur after 5 years of age when oral penicillin prophylaxis has been terminated.

Neonatal BO Incompatibility Is Associated With a Positive Cord Blood Direct Antiglobulin Test in Infants of Black Ethnicity.

ABO hemolytic disease of the newborn occurs almost exclusively in infants of blood group A and B who are born to group O mothers. Positive Direct Antiglobulin Test (DAT) can identify those infants who are at risk of developing the ABO hemolytic disease. Earlier studies have suggested that BO incompatibility is associated with a positive DAT in black infants. In this study we sought to determine whether ABO incompatibility type could be associated with a higher rate of DAT positivity or clinical hemolytic disease. We reviewed the electronic medical records of all ABO-incompatible births over a 2-year period. There were 1537 ABO-incompatible births during the study period. DAT was more commonly positive among BO incompatible (21.5% in BO vs. 14.8% in AO, P=0.001) and black (18.8% in blacks vs. 10.8% in nonblacks, P=0.003) infants. DAT positivity was significantly associated with both severe hyperbilirubinemia (P=0.028) and hemolytic anemia (P<0.001). BO incompatibility was significantly associated with hemolytic anemia, but not severe hyperbilirubinemia, in the infants tested.

Emergency department visits in children with hemophilia.

BACKGROUND: The pediatric emergency department (ED) management of bleeding and other complications of hemophilia constitutes an increasingly important component of hemophilia therapy. This retrospective study examined the overall ED use by children with hemophilia in a single center, with a particular aim to investigate visits related to injury or bleeding, and those related to blood stream infection in patients with a central venous catheter (CVC). METHODS: Electronic medical records of patients with hemophilia presenting to Children's Hospital of Michigan ED were reviewed. Different categories of ED visits over a 5-year period (January 2006-December 2010) were examined. RESULTS: There were 536 ED visits from 84 male patients (median age 4 years, range 0-21) with hemophilia over the 5-year period. The reasons for ED visits were: injury or bleeding (61.2%); suspected CVC-related infection (11.8%); causes unrelated to hemophilia (19.2%); and routine clotting factor infusion (7.8%). Eighteen visits from six patients were secondary to injury or bleeding in a patient not yet diagnosed with hemophilia. An intracranial hemorrhage was detected in five visits. Overall, 5.4% of all visits represented distinct episodes of bloodstream infection. CONCLUSION: The pediatric ED is an indispensable component of the overall hemophilia care, because: (1) patients with potentially lethal problems such as ICH or CVC-related infection may present to the ED for their initial management; (2) previously undiagnosed patients with hemophilia may also present to the ED for their first bleeding episodes, initiating the diagnostic investigations; (3) the ED provides after-hours treatment service for many episodes of injury or bleeding, and also for clotting factor infusion.

The efficiency of gabapentin therapy in patients with lumbar spinal stenosis.

STUDY DESIGN: Randomized controlled study. OBJECTIVES: To investigate the efficacy of treatment with gabapentin on the clinical symptoms and findings in patients with lumbar spinal stenosis (LSS). SUMMARY OF BACKGROUND DATA: LSS is a syndrome resulting from the narrowing of the lumbar nerve root canal, spinal canal, and intervertebral foramen, causing compression of the spinal cord. The most significant clinical symptom in patients with LSS is neurologic intermittent claudication (NIC). Gabapentin, which has been used in the treatment of neuropathic pain, may be effective in the treatment of symptoms associated with LSS. METHODS: Fifty-five patients with LSS, who had NIC as the primary complaint, were randomized into 2 groups. All patients were treated with therapeutic exercises, lumbosacral corset with steel bracing, and nonsteroidal anti-inflammatory drugs. The treatment group received gabapentin orally in addition to the standard treatment. RESULTS: Gabapentin treatment resulted in an increase in the walking distance better than what was obtained with standard treatment (P = 0.001). Gabapentin-treated patients also showed improvements in pain scores (P = 0.006) and recovery of sensory deficit (P = 0.04), better than could be attained with the standard treatment. CONCLUSION: Based on the results of our pilot study, extensive clinical studies are warranted to investigate the role of gabapentin in the management of symptomatic LSS.

Vacuolated neuroblastoma cells mimicking FAB L(3) lymphoblasts in bone marrow aspirates.

Abundant cytoplasmic vacuolation of neuroblasts has been noted on bone marrow aspirate (BMA) smears of two patients with metastatic neuroblastoma. Occasional tumor cells were dispersed as individual cells as well as in clumps. These cells had basophilic cytoplasm and several nucleoli, reminiscent of L(3) lymphoblast morphology. Flow cytometric analysis of the bone marrow mononuclear cells and neuron-specific enolase staining of the bone marrow biopsy samples further distinguished the cells as neuroblasts. Cytoplasmic vacuolations of neuroblasts may be a feature of metastatic neuroblastoma cells in BMA smears.

Defining the role of magnetic resonance imaging in unifocal bone lesions of langerhans cell histiocytosis.

Localized Langerhans cell histiocytosis (LCH) of bone often presents as a diagnostic challenge. Magnetic resonance imaging (MRI) is frequently used to better delineate most solitary bony lesions. The authors present two cases that illustrate and better define the role of MRI in the evaluation of solitary bone lesions of LCH. In a 3-year-old boy with left-sided hip pain, MRI showed a focal lesion involving the proximal left femur with low signal intensity on T1-weighted images and high signal intensity on T2-weighted images. A tumor was suspected because of the overall imaging characteristics and increased uptake on three-phase nuclear scintigraphy. In a 6-year-old boy with right thigh pain, MRI showed a fluid-containing lesion in the mid-diaphysis of the right femur, suggestive of chronic osteomyelitis and Brodie abscess. MRI was instrumental in showing the extent of the lesions in both cases; however, the final diagnosis of LCH was achieved only with histopathologic confirmation, illustrating the limited diagnostic power of this imaging tool.

Pediatric EBV-positive T-cell/histiocyte-rich large B-cell lymphoma with clonal cells in the bone marrow without overt involvement.

T-cell/histiocyte-rich large B-cell lymphoma (TCHRLBCL) is a variant of large B-cell lymphoma only rarely encountered in children. Here we report the case of an 8-year-old African American boy with Epstein-Barr virus (EBV)-positive TCHRLBCL who initially presented with right submandibular, anterior cervical and supraclavicular lymphadenopathy. Cytogenetic analysis of the lymph node revealed a near-triploid karyotype with complex chromosomal aberrations. Although morphologically the bone marrow was normal, the same cytogenetically abnormal clone was detected. The patient responded to chemotherapy with CHOP (doxorubicin, cyclophosphamide, vincristine and prednisone) therapy, with disappearance of the abnormal clone from the bone marrow. The patient remains in remission 26 months after the initial diagnosis.