Is Your Kid Actin Out? A Series of Six Patients With Inherited Actin-Related Protein 2/3 Complex Subunit 1B Deficiency and Review of the Literature.

BACKGROUND: Hereditary actin-related protein 2/3 complex subunit 1B deficiency is characterized clinically by ear, skin, and lung infections, bleeding, eczema, food allergy, asthma, skin vasculitis, colitis, arthritis, short stature, and lymphadenopathy. OBJECTIVE: We aimed to describe the clinical, laboratory, and genetic features of six patients from four Mexican families. METHODS: We performed exome sequencing in patients of four families with suspected actinopathy, collected their data from medical records, and reviewed the literature for reports of other patients with actin-related protein 2/3 complex subunit 1B deficiency. RESULTS: Six patients from four families were included. All had recurrent infections, mainly bacterial pneumonia, and cellulitis. A total of 67% had eczema whereas 50% had food allergies, failure to thrive, hepatomegaly, and bleeding. Eosinophilia was found in all; 84% had thrombocytopenia, 67% had abnormal-size platelets and anemia. Serum levels of IgG, IgA, and IgE were highly increased in most; IgM was normal or low. T cells were decreased in 67% of patients, whereas B and NK cells were increased in half of patients. Two of the four probands had compound heterozygous variants. One patient was successfully transplanted. We identified 28 other patients whose most prevalent features were eczema, recurrent infections, failure to thrive, bleeding, diarrhea, allergies, vasculitis, eosinophilia, platelet abnormalities, high IgE/IgA, low T cells, and high B cells. CONCLUSION: Actin-related protein 2/3 complex subunit 1B deficiency has a variable and heterogeneous clinical spectrum, expanded by these cases to include keloid scars and Epstein-Barr virus chronic hepatitis. A novel deletion in exon 8 was shared by three unrelated families and might be the result of a founder effect.

[Penicillin allergy]. / Alergia a la penicilina.

Betalactams are the most widely used antimicrobials for their safety and efficacy. These include the penicillins, cephalosporins, carbapenems, and monobactams. Penicillin allergy ranks first in relation to drug allergy. 10 to 20 % of the population is labeled as allergic to it, often wrongly. Cross reaction is reported in 2 to 5 % between penicillins and cephalosporin. There is no cross reaction between penicillins and aztreonam, but there is with ceftazidime. All the mechanisms of the Gell and Coombs classification are included in the pathophysiology of hypersensitivity reactions to penicillin. Stratification according to risk allows us to take the most objective behavior to label the patient as allergic to. In the natural history of penicillin allergy, 80-90 % of patients lose this sensitivity by 10 years. If necessary, the patient can undergo a desensitization protocol. The immuno-allergist is a key piece in the selection of the patient, the elaboration of the challenge and desensitization protocols, in a controlled environment.

Los betalactámicos son los antimicrobianos más utilizados por su seguridad y eficacia. En este grupo se incluyen las penicilinas, las cefalosporinas, los carbapenémicos y los monobactámicos. La penicilina constituye la primera causa de alergia a medicamentos: 10 a 20 % de la población se etiqueta como alérgica a la misma, en muchas ocasiones erróneamente. Se ha reportado reacción cruzada entre penicilinas y cefalosporina en 2 a 5 %. No hay reacción cruzada entre penicilinas y aztreonam, pero sí con ceftazidima. En la fisiopatología de las reacciones de hipersensibilidad a penicilina se incluyen todos los mecanismos de la clasificación de Gell y Coombs. La estratificación de acuerdo con el riesgo permite tomar la decisión más objetiva para etiquetar al paciente como alérgico. En la evolución natural de la alergia a la penicilina, 80 a 90 % de los pacientes pierde dicha sensibilidad a los 10 años. De ser indispensable, el paciente puede ser sometido a un protocolo de desensibilización. El médico inmunoalergologo es una pieza clave en la selección del paciente, la elaboración de los protocolos de reto y la desensibilización en un ambiente controlado.

Recurrent Toxic Epidermal Necrolysis Syndrome: A Report of Two Cases.

An 81-year-old male and a 47-year-old female experienced recurrent severe bullous dermatosis secondary to an intake of drugs and alternative medicines indicated for arthralgias. The first patient had previously presented with Stevens-Johnson/toxic epidermal necrolysis (TEN) overlap syndrome in 2007 secondary to ingestion of trimethoprim/sulfamethoxazole indicated for a urinary tract infection; 6 years later, he presented with the same syndrome 2 days after ingestion of oral naproxen tablets 250 mg twice daily. The second patient had presented 5 years previously with TEN after receiving trimethoprim/sulfamethoxazole. In 2014, she presented with arthralgias and received a xenobiotic oral called 'miracle pills' (dosage is unknown); 3 weeks later, she again experienced TEN. Both patients were treated with intravenous immunoglobulin 400 mg/kg/day; duration of treatment was 5 days for the first patient and 3 days for the second. However, the male patient died from severe sepsis; the female patient experienced a favorable outcome. There are many risk factors for the development of cutaneous adverse drug reactions; a history of allergic reactions is one important risk factor, and both patients had it. This article reviews the scientific literature on this topic and analyzes the possible causes, including infectious processes, immunological defects, and immunogenetic factors.