Erythropoietin-stimulating agent-resistant vitamin B6 deficiency anemia in a pediatric patient on hemodialysis.

BACKGROUND: Vitamin B6 is a rate-limiting coenzyme that plays an important role in the biosynthesis of heme and the incorporation of iron into protoporphyrin. Its deficiency is often seen in chronic kidney disease (CKD), particularly those requiring dialysis and following administration of erythropoietin-stimulating agent (ESA). CASE- DIAGNOSIS/TREATMENT: A 16-year-old African-American male with stage 5 CKD on chronic hemodialysis experienced a decrease in hemoglobin over a 3-month period from 11 to 6.5 g/dl while receiving ESA, resulting in multiple blood transfusions. His transferrin saturation was 41%, ferritin level 706 [80-388] ng/mL, mean corpuscular volume (MCV) 87 [78-98] µm3, corrected reticulocytes count 2.3% [0.2-1.8%], and vitamin B6 1.2 [5.3-46.7] µg/L. Bone marrow biopsy was normocellular (65%) with erythroid hyperplasia and rare dyserythropoiesis. Prussian blue staining showed increased iron storage. Supplemental vitamin B6 (100 mg daily) was initiated at hemoglobin 7.3 g/dL with correction of anemia. Eighteen months later, his hemoglobin is 11.7 g/dL, transferrin saturation 45%, with no additional blood transfusions. CONCLUSIONS: Vitamin B6 deficiency anemia should be considered in any pediatric patient on hemodialysis who does not respond to standard ESA and iron therapy.

A 14-year-old boy with extranodal natural killer cell lymphoma of the nose, nasopharynx, larynx, and trachea in remission 6years after primary diagnosis. A longitudinal case report.

Nasal type extranodal natural killer/T-cell lymphoma (ENKTL) is a rare lymphoma in the USA and Europe but endemic in East Asia and in areas of South and Central America. Clinically natural killer cell lymphomas are divided into three categories; nasal, non-nasal and aggressive lymphoma/leukemia subtypes. ENKTL, nasal type occurs in the nose and can extend to the upper aero-digestive tract as reported in this longitudinal case study. This is a longitudinal report of progress of a 14-year-old boy with ENKTL originating in the nasal cavity with subsequent extension and recurrence in the contralateral nose, nasopharynx, larynx and trachea presenting with varying degrees of respiratory problems and eventually, respiratory distress. Caregiver refusal of stem cell transplantation prompted an alternative diagnostic and therapeutic approach. Clinical course with recurrences, extensions and remissions over 6years with tailored endoscopic surgical treatment and radiochemotherapy is documented to present a guide in the multidisciplinary management of this rare disease.

Successful treatment of relapsing autoimmune thrombotic thrombocytopenic purpura with rituximab.

Thrombotic thrombocytopenic purpura (TTP) is a rare but life-threatening condition characterized by thrombotic microangiopathy. The standard treatment for TTP is plasmapheresis. For refractory or relapsing cases, various immunosuppressive agents have been tried, and among them rituximab has shown promising results. TTP is rarer in the pediatric age group and the use of rituximab in children with TTP is limited. Reported herein is the successful treatment of relapsing autoimmune TTP with rituximab in a 12-year-old girl.

Langerhans cell histiocytosis, a case of Letterer Siwe disease.

An 8-month-old male infant presented with a progressively worsening generalized rash of 5-6 months duration, fever, poor feeding, and abdominal distension. An initial laboratory workup revealed anemia, thrombocytopenia, and hepatosplenomegaly. The patient was started on i.v. antibiotics, and a working diagnosis of Langerhans cell histiocytosis was reached that was later confirmed with a skin biopsy. Subsequently, the patient received first-round chemotherapy with vinblastine and prednisone, on which he appeared to improve clinically; however, he soon relapsed. He then received combination salvage therapy with cladribine (2CdA) and cytarabine (Ara-C) for three cycles. The patient responded well to this regimen with resolution of his condition. The patient was then referred for a bone marrow transplant.

Epstein-Barr virus induced hemophagocytic lymphohistiocytosis in X-linked lymphoproliferative disease.

X-linked lymphoproliferative disease (XLP) is a rare, often fatal genetic disorder characterized by extreme vulnerability to Epstein-Barr virus (EBV). EBV-induced hemophagocytic lymphohistiocytosis (HLH) is a known presentation in XLP. In EBV-induced HLH in XLP, the brain imaging findings in the acute phase include a non specific pattern. In this report, we highlight the magnetic resonance imaging and magnetic resonance spectroscopy findings in a child with EBV induced HLH in XLP.

Maxillofacial extramedullary hematopoiesis in a child with sickle cell presenting as bilateral periorbital cellulitis.

Review of a case of paraosseous extramedullary hematopoiesis (EMH) affecting the maxillary sinuses and retro-orbital spaces imitating bilateral orbital cellulitis. Maxillofacial EMH causes diagnostic/therapeutic challenges. This case report describes a 4-year-old African American male with sickle cell disease (HbSS) who presented with bilateral orbitofacial swelling. Diagnosis was made with imaging and confirmed with tissue sampling. Partial exchange transfusion was utilized to stop the progression of maxillofacial EMH and to treat the patient's chronic anemia. Follow-up MRI showed regression of orbital and retro-orbital involvement. Early treatment with conservative modalities and close observation may prevent need for more invasive treatments.

Primary calvarial angiosarcoma: A case report and review of the literature.

BACKGROUND: Angiosarcomas are high-grade endothelial tumors remarkable for their rarity and malignant behavior. Primary calvarial angiosarcoma is an extremely rare entity and its behavior usually sets it apart from other angiosarcoma types. We highlight the successful management of cranial angiosarcoma using a multidisciplinary approach. CASE DESCRIPTION: We present a 16-year-old male who was first noted to have a right-sided parietal cranial mass that was biopsied in 2008. Pathology was initially thought to be Kaposiform hemangioendothelioma. The patient subsequently underwent chemotherapy with vincristine. The patient did well until early 2010, when he suffered a right-sided intraparenchymal intratumoral hemorrhage. At this time, the original pathologic diagnosis was revisited and the diagnosis was upgraded to an angiosarcoma. The patient underwent a second round of chemotherapy using vincristine, cyclophosphamide, and actinomycin. The tumor continued to progress despite this treatment and he developed extensive skull deformity. At this point more definitive surgical intervention was reconsidered. Preoperative embolization of the mass was performed followed by aggressive surgical resection of the bony disease. The patient tolerated the procedure well and was discharged 6 days postoperatively without any new deficits. The patient is currently in the process of completing radiation therapy to entire tumor bed. He has clinically done well with no neurologic deterioration and has demonstrated long-term survival (>3 years). CONCLUSION: With the combined efforts of pediatric oncology, radiation oncology, interventional neuroradiology, and neurosurgery, a survival of greater than 3 years is possible with this aggressive pathology.

A boy with fever, lymphadenopathy, hepatosplenomegaly, and lymphocytosis.

Proliferation of the lymphoid system should arouse suspicion of a potentially serious illness. We present a 4.5-year-old boy who developed fever, vomiting, diarrhea, lymphadenopathy, hepatosplenomegaly, lymphocytosis, anemia, thrombocytopenia, and increased liver enzymes. Lymph node and bone marrow biopsies showed lymphoproliferation, Epstein-Barr virus (EBV) infection, and hemophagocytosis leading to the diagnosis of hemophagocytic lymphohistiocytosis (HLH). Chemotherapy was initiated for HLH with dexamethasone, etoposide, and cyclosporine. Because of a high level of EBV viremia, rituximab was added a few days later and resulted in a remarkable drop in the EBV in the circulation but not in the cerebrospinal fluid. However, the patient succumbed to encephalitis, pneumonia, and cardiopulmonary failure. Autopsy revealed the presence of EBV in the brain, indicating the ineffectiveness of rituximab therapy in treating central nervous system infection with EBV.

Cerebral lymphoma in an adenosine deaminase-deficient patient with severe combined immunodeficiency receiving polyethylene glycol-conjugated adenosine deaminase.

Polyethylene glycol-conjugated adenosine deaminase (PEG-ADA) provides an alternate therapy to mismatched stem cell transplantation for patients with ADA-deficient severe combined immunodeficiency. Although replacement therapy with PEG-ADA is effective in preventing infections, immune function does not return to normal, and most patients remain lymphopenic. Information is limited regarding the prognosis of patients on long-term ADA-replacement therapy. Here we present a case of a 10-year-old child who was diagnosed with ADA-severe combined immunodeficiency at 4 weeks of age after contracting pneumonia. Treatment with PEG-ADA was begun, the biochemical markers of ADA deficiency normalized, and his clinical progress was very good without significant infections. At 10 years of age, after presenting with headaches and cranial nerve deficits, he was diagnosed with Epstein-Barr virus-positive malignant brain lymphoma. It did not respond to various regimens of aggressive chemotherapy, and the patient expired 5 months later. We speculate that in this patient the immunologic surveillance by T cells may have been defective with respect to elimination of Epstein-Barr virus-infected cells, hence the formation of neoplasm. The possible mechanisms underlying such pathology are reviewed.