Successful hematopoietic cell transplantation in a patient with X-linked agammaglobulinemia and acute myeloid leukemia.

X-linked agammaglobulinemia (XLA) is a primary immunodeficiency characterized by marked reduction in all classes of serum immunoglobulins and the near absence of mature CD19(+) B-cells. Although malignancy has been observed in patients with XLA, we present the first reported case of acute myeloid leukemia (AML) in a patient with XLA. We also demonstrate the complete correction of the XLA phenotype following allogeneic hematopoietic cell transplantation for treatment of the patient's leukemia.

Insect repellents and contact urticaria: differential response to DEET and picaridin.

Topical insect repellent is commonly used throughout the world. Active ingredients typically include N,N-diethyl-meta-toluamide (DEET) or picaridin. Reactions to topical repellents have ranged from contact dermatitis to urticaria. Exposure to DEET can produce contact urticaria; however, it is unknown if patients with a sensitivity to DEET can tolerate picaridin. We report the case of a 22-year-old man who presented for evaluation of contact urticaria that had developed immediately after the application of insect repellent and contact with individuals who had used DEET-containing repellents. No systemic manifestations were noted. Commercially available products containing DEET or picaridin were used for open patch testing. The patient showed immediate urticarial responses to 7% DEET and 7% DEET in ethanol, but patch tests for 5% picaridin and 5% picaridin in ethanol were negative. Based on these results, we conclude that insect repellents containing picaridin may be acceptable alternatives in patients who demonstrate sensitivity to products containing DEET.

Association of natural killer cell dysfunction and recurrent Stevens-Johnson syndrome in a pediatric patient.

Stevens-Johnson syndrome (SJS) is a debilitating condition involving the skin and mucous membranes. It is commonly the result of adverse drug reactions but can also be caused by infections. A predisposition to recurrent viral infections, such as in the case of natural killer (NK) cell dysfunction, may manifest with virally induced SJS. We present this case to suggest a possible association between NK cell dysfunction and recurrent SJS. An 11-year-old girl presents with recurring erythema, erosion, and ulceration of oral and vaginal mucosa. Small fluid-filled bumps would appear, leading to blistering and later sloughing of mucosal tissue, and bleeding would ensue. Seven separate episodes have occurred over an 8-year period, with each episode being preceded by symptoms of an upper respiratory infection. NK cell function assays were performed and NK cell phenotyping was ordered. NK cell assays showed decreased NK cell cytotoxicity at all ratios of K562 target cells. NK cell surface expression evaluation showed an immature phenotype but normal overall numbers of NK cells. NK cells are a pivotal part of the innate immune system, and, among other things, provide defense of viral infection. This case represents the manifestation of recurrent SJS as a result the lack of protection from viral illness, usually provided by NK cells in the healthy immune system.

The rate of epinephrine administration associated with allergy skin testing in a suburban allergy practice from 1997 to 2010.

Allergy skin testing is considered a safe method for testing for IgE-mediated allergic responses although anaphylactic events can occur. Reported rates of anaphylaxis per patient are not consistent and range from 0.008 to 4%. The aim of this study was to determine the rate of epinephrine use associated with allergy skin-prick testing (SPT) and intradermal testing (IDT) in a suburban practice over 13 years. This retrospective chart review used billing and procedure coding records during the time period from January 1997 to June 2010 to identify encounters where epinephrine was administered after SPT or IDT. Patient encounters with procedure codes for skin testing plus either parenteral epinephrine, corticosteroid, antihistamine, or i.v. fluid administration were identified. These patient charts were reviewed to determine if epinephrine was administered, whether systemic reactions developed, and rates of epinephrine administration were calculated. There were 28,907 patient encounters for SPT and 18,212 for IDT. Epinephrine was administered in six patient encounters (0.02%) where SPT was performed; no IDT encounters led to epinephrine administration. There were no fatalities. Allergy skin testing to a variety of allergens, when administered by well-trained personnel, is a safe procedure. This study, involving the largest population to date, showed a rate of systemic reactions requiring epinephrine of 20 per 100,000 SPT visits. No epinephrine was given after IDT.

Signal transducer and activator of transcription 3 mutation with invasive eosinophilic disease.

Hyper-IgE syndrome (HIES), or Jobs disease, is a rare immunologic disorder characterized by the triad of staphylococcal abscesses, pneumonia with pneumatocele formation, and elevated IgE. It has been shown to have multiple modes of inheritance, autosomal dominant being more common than autosomal recessive, with sporadic cases as well. A mutation in signal transducer and activator of transcription 3 (STAT3) gene has been linked to the development of the sporadic and dominant forms of HIES. Peripheral eosinophilia, typically greater than two standard deviations from the normal population, is often seen in association with HIES. Despite these elevated levels of blood eosinophils, there have been no reported cases of invasive eosinophilic disease, such as eosonophilic esophagitic. Here we report the first description, to our knowledge, of a patient with HIES with a STAT3 mutation involving exon 12, Thr389Ile, and invasive eosinophilic disease of the esophagus. STAT3 modulates the expression of several genes that control central cell processes such as growth and death in response to external soluble stimuli. A mutation in the STAT3 molecule may affect the eosinophil's response to IL-5 and thus reduce the chemotaxic ability of those cells to migrate into tissues. This may then explain the paucity of eosinophilic infiltrative disease in patients with STAT3 mutations. The level of eosinophilic involvement may be related to the site or type of mutation within the STAT3 molecule. As more data are collected, we may be able to assess whether certain mutations dictate different clinical outcomes, which could prove helpful in directing therapy.

Cracking the shell on egg-hypersensitive patients and egg-containing vaccines.

Hens' eggs are a common food in the American diet. They are consumed as a primary food source and added as an ingredient to other foods. In individuals who are hypersensitive to eggs, egg-containing foods can cause mild to severe allergic reactions if ingested. These individuals may also have adverse reactions to vaccines produced on egg media. Vaccines that are created on egg media include those for measles, mumps, and rubella; rabies; yellow fever; and influenza. The authors discuss recent developments in the use of egg-containing vaccines in hypersensitive patients.