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.

Methimazole Induced Total Myeloid Aplasia with Delayed Recovery Despite Granulocyte Colony Stimulating Factor (G-CSF): Marrow Progenitor Recovery Kinetics.

An eighteen-year-old female with Graves thyrotoxicosis presented with methimazole-induced agranulocytosis and total myeloid aplasia. The bone marrow at presentation showed complete absence of myeloid precursors and striking plasmacytosis. 16 days later, myeloid precursors were still absent morphologically; however bone marrow flow cytometry and cell culture detected an improvement in myelogenesis, which was soon followed by clinical recovery of agranulocytosis. Neutrophil recovery was delayed until day 22 after cessation of methimazole despite G-CSF use, consistent with a direct toxic effect on committed myeloid cells. Our findings suggest that cell culture and flow cytometric evaluation of bone marrow myeloid progenitors can be used as a guide to anticipate neutrophil recovery.

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.

Upper-extremity deep venous thrombosis after whole blood donation: report of three cases from a single blood center.

BACKGROUND: There are two upper-extremity deep venous thrombosis (UEDVT) cases after whole blood donation reported in the English medical literature. Three additional UEDVT cases after whole blood donation were reported to our blood center within a 13-month period. STUDY DESIGN AND METHODS: A case study was done for each case in collaboration with a clinical physician. A description of the donation event, donor demographics, risk factors for thrombosis, treatment, and outcome were described. RESULTS: A 33-year-old woman and two 17-year-old, first-time-donating men presented with arm pain, swelling, and bruising within hours to 3 days after donation. Two had distal UEDVTs in the basilic or brachial veins, and one had a proximal UEDVT in the subclavian and axillary veins extending into the basilic vein. One donor (woman) had known risk factors for DVT and the other two did not. Anticoagulant therapy was initiated on all patients and was continued for 3, 4, and 9 months. Two donors with the distal UEDVTs recovered completely while the donor with the proximal UEDVT was treated with anticoagulation for 9 months and continued to have a slight residual, nonobstructive thrombosis. The donor was switched to low-dose aspirin prevention. The two donors reported in the literature had complete resolution of thrombosis. CONCLUSIONS: Four of five donors recovered completely after anticoagulation treatment for UEDVT, including two of three donors in this study. A review of all cases in the medical literature, including 20 recent Australian cases described in an abstract, provides a more complete description of this adverse donation injury.

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.

Provocative F wave in the diagnosis of nonspecific neurogenic-type thoracic outlet syndrome.

OBJECTIVE: Thoracic outlet syndrome (TOS) is defined as a constellation of clinical symptoms caused by the entrapment of neurovascular structures (subclavian vessels and the brachial plexus) en route to the upper limb via the superior thoracic outlet. Nonspecific neurogenic TOS is not easy to diagnose because there is no investigational technique that has proven to be the diagnostic gold standard. DESIGN: In this study, our aim was to investigate the role of provocative F response in the diagnosis of nonspecific neurogenic TOS. F wave analysis of median and ulnar nerves in neutral and provocative maneuvers was carried out in 21 patients with a clinical diagnosis of nonspecific neurogenic TOS and in 15 healthy volunteers. RESULTS: All findings were within reference range in both groups, and no statistical difference was noted among subject groups, with or without provocative maneuvers. CONCLUSIONS: We conclude that the nonspecific neurogenic TOS is a temporary compression process that does not result in a structural damage on the nerve; therefore, significant electrophysiologic changes are not elicited.

Warfarin reversal emerging as the major indication for fresh frozen plasma use at a tertiary care hospital.

Because of the increase in the use of warfarin in the population in recent years, reversal of warfarin-related coagulopathy has become common in daily hospital practice. Transfusion of fresh frozen plasma (FFP) is the preferred treatment method for urgent warfarin reversal in the USA. We have undertaken a 1-month audit of FFP usage to ascertain the impact of warfarin use on the consumption of FFP. Sixty percent of the 376 units of FFP that were transfused during the study month were used to reverse warfarin effects. The most common reason to reverse warfarin was bleeding. Thirty-three percent of the units were used for the treatment of other coagulopathies, 7% were used in therapeutic plasmapheresis, and <1% was transfused empirically. One hundred and eighteen patients received FFP during the study month. The study population consisted mostly of elderly patients (65%); however, the warfarin reversing patients consisted disproportionately more of elderly patients (75%) compared with patients receiving FFP for other reasons (46%) (P = 0.0032). Warfarin reversal emerged as the major indication for FFP use in this study. Blood banks of hospitals serving a predominantly elderly patient population should anticipate a higher consumption of FFP. Careful monitoring of warfarin therapy, stringent implementation of the warfarin reversal guidelines, and the introduction of newer products for warfarin reversal would help reduce the consumption of FFP.

An audit on the current practice of red blood cell transfusion following elective primary hip arthroplasty.

This audit encompassing a six-month period on the current practice of red blood cell transfusion following elective primary total hip arthroplasty showed that the rate of allogeneic blood avoidance was 84.8% for preoperative autologous blood donors and 47.8% for non-donors (p<0.001). Lower preoperative hemoglobin level was associated with an increased allogeneic unit transfusion (p<0.001). The intraoperative use of autologous blood collection and transfusion systems did not reduce the transfusion risk, and the use of the colloid volume expander was associated with a 1.8-fold increased risk of transfusion (p=0.022).

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.

How do you treat bleeding disorders with desmopressin?

Desmopressin is an analog of vasopressin that exerts a substantial haemostatic effect by inducing the release of von Willebrand factor from its storage sites in endothelial cells. It has proved useful in treating or preventing bleeding episodes in patients with von Willebrand disease, haemophilia A and platelet function defects. Its efficacy in achieving a satisfactory level of haemostasis has reduced the use of blood products to treat bleeding episodes. Clinicians need to become familiar with the use of this drug that has become a home medication for many patients with inherited bleeding disorders.

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.