Dapsone-induced methemoglobinemia in pediatric oncology patients: case examples.

Over the last 25 years, significant advances have been made in supportive care of the immunocompromised patient. One significant advance is the use of trimethoprim-sulfamethoxazole (TMP-SMZ) in the prevention of Pneumocystic carinii pneumonia (PCP). Although TMP-SMZ remains the drug of choice for PCP prophylaxis, children who develop or have a history of adverse reactions must be prescribed an alternative treatment. In these instances, medications such as dapsone, aerosolized pentamidine, or atovaquone are prescribed. This report discusses four children with sulfa allergy who were prescribed dapsone and later developed methemoglobinemia. Although methemoglobinemia is associated with dapsone, there was no reference found regarding this link in the pediatric oncology literature. The purpose of these clinical examples is to alert the pediatric nurse and advanced practitioner to the association of dapsone and methemoglobinemia.

Pilot study of noninvasive detection of venous occlusions from central venous access devices in children treated for acute lymphoblastic leukemia.

BACKGROUND: Survivors of childhood acute lymphocytic leukemia (ALL) are at risk of venous occlusion induced by central venous access devices (CVADs). A sensitive, noninvasive screening technique to identify the magnitude of this problem is needed. Ultrasound (US) cannot always adequately image the innominate veins or the superior vena cava. Magnetic resonance angiography (MRA) can be noninvasive and may be useful for screening these patients. OBJECTIVE: We examined the suitability of US and MRA to identify venous occlusion. MATERIALS AND METHODS: We used MRA and ultrasound to examine 11 pediatric patients previously treated for ALL. CVADs had been in place a median of 2.5 years (range, 0.4-2.8 years) and removed a median of 2.1 years (range, 0.6-2.9 years) previously. We also performed 2D time-of-flight magnetic resonance angiography (TOF MRA) on two healthy young adult women with no history of venous abnormality or CVAD use. RESULTS: MRA suggested central venous abnormalities in 8 of the 11 ALL survivors and in both healthy control subjects. US results were negative in all 11 survivors. CONCLUSION: Further investigation is warranted to develop a sensitive and specific noninvasive method for identifying venous occlusion caused by prior CVAD use. Such a method would allow prospective studies of this complication in pediatric ALL survivors.

Aluminum toxicity following intravesical alum irrigation for hemorrhagic cystitis.

Mental status changes in an immunosuppressed child can be due to a variety of causes; aluminum toxicity is rarely considered. We report a teenage girl with acute lymphoblastic leukemia who developed mental status changes, speech disturbance, coarse tremor, and abnormal EEG findings following intravesical 1% alum irrigation and administration of aluminum-containing antacids. Her serum aluminum levels were mildly elevated (14-22 milligram(s), normal 0-6 milligram(s)), and bone marrow biopsy specimens demonstrated aluminum deposition on special staining (Krueger's method). All abnormalities resolved after a nine-week course of intravenous deferoxamine.

Effectiveness of paclitaxel in treating papillary serous carcinoma of the peritoneum in an adolescent.

A 15-year-old girl with papillary serous carcinoma of the peritoneum was seen with abdominal distention, ascites, and elevated CA 125 tumor marker. After other therapy failed, she achieved complete and continuing remission with paclitaxel.