Evaluating bronchodilator response in pediatric patients with post-infectious bronchiolitis obliterans: use of different criteria for identifying airway reversibility

OBJECTIVE

Post-infectious bronchiolitis obliterans (PIBO) is a clinical entity that has been classified as constrictive, fixed obstruction of the lumen by fibrotic tissue. However, recent studies using impulse oscillometry have reported bronchodilator responses in PIBO patients. The objective of this study was to evaluate bronchodilator responses in pediatric PIBO patients, comparing different criteria to define the response.

METHODS

We evaluated pediatric patients diagnosed with PIBO and treated at one of two pediatric pulmonology outpatient clinics in the city of Porto Alegre, Brazil. Spirometric parameters were measured in accordance with international recommendations.

RESULTS

We included a total of 72 pediatric PIBO patients. The mean pre- and post-bronchodilator values were clearly lower than the reference values for all parameters, especially FEF25-75%. There were post-bronchodilator improvements. When measured as mean percent increases, FEV1 and FEF25-75%, improved by 11% and 20%, respectively. However, when the absolute values were calculated, the mean FEV1 and FEF25-75% both increased by only 0.1 L. We found that age at viral aggression, a family history of asthma, and allergy had no significant effects on bronchodilator responses.

CONCLUSIONS

Pediatric patients with PIBO have peripheral airway obstruction that is responsive to treatment but is not completely reversible with a bronchodilator. The concept of PIBO as fixed, irreversible obstruction does not seem to apply to this population. Our data suggest that airway obstruction is variable in PIBO patients, a finding that could have major clinical implications.

OBJETIVO

A bronquiolite obliterante pós-infecciosa (BOPI) é uma entidade clínica que tem sido classificada como obstrução fixa e constritiva do lúmen por tecido fibrótico. Entretanto, estudos recentes utilizando oscilometria de impulso relataram resposta ao broncodilatador em pacientes com BOPI. O objetivo deste estudo foi avaliar a resposta broncodilatadora em pacientes pediátricos com BOPI, comparando critérios diferentes para a definição da resposta.

MÉTODOS

Foram avaliados pacientes pediátricos com diagnóstico de BOPI tratados em um de dois ambulatórios de pneumologia pediátrica na cidade de Porto Alegre (RS). Parâmetros espirométricos foram medidos de acordo com recomendações internacionais.

RESULTADOS

Foram incluídos 72 pacientes pediátricos com BOPI no estudo. As médias dos valores pré- e pós-broncodilatador foram claramente inferiores aos valores de referência para todos os parâmetros, especialmente FEF25-75%. Houve uma melhora pós-broncodilatador. Quando medidos como aumentos percentuais médios, VEF1 e FEF25-75% melhoraram em 11% e 20%, respectivamente. Entretanto, quando os valores absolutos foram calculados, as médias de VEF1 e FEF25-75% aumentaram somente em 0,1 l. Verificamos que a idade da agressão viral, história familiar de asma e alergia não tiveram efeitos significativos na resposta ao broncodilatador.

CONCLUSÕES

Pacientes pediátricos com BOPI têm uma obstrução das vias aéreas periféricas que responde ao tratamento, mas não uma reversão completa com o broncodilatador. O conceito de BOPI como obstrução fixa e irreversível parece não se aplicar a essa população. Nossos dados sugerem que a obstrução de vias aéreas em pacientes com BOPI é variável, e esse achado pode ter importantes implicações clínicas.

Acute myocardial infarction associated with nonbacterial thrombotic endocarditis

Herein, we describe the cases of 4 patients who each experienced a myocardial infarction in association with nonbacterial thrombotic endocarditis. We discuss the clinical presentation of this rare condition, distinguish between infective and nonbacterial thrombotic endocarditis via a review of the medical literature, and present treatment options for myocardial infarction that is associated with nonbacterial thrombotic endocarditis.

Endovascular exclusion of mycotic aortic aneurysm

The presence of prohibitive risk may preclude usual surgical management. Such was the case for a critically ill, 60-year-old woman who presented with concomitant, life-threatening conditions. The patient presented with acute central cord syndrome and lower-extremity paraplegia after completing a 6-week course of intravenous antibiotics for methicillin-sensitive Staphylococcus aureus bacteremia and osteomyelitis of the thoracic spine. Radiologic examination revealed bony destruction of thoracic vertebrae T4 through T6, impingement on the spinal cord and canal by an inflammatory mass, and a separate 2.5-cm mycotic aneurysm of the infrarenal aorta. The clinical and radiologic findings warranted immediate decompression and stabilization of the spinal cord, aneurysmectomy, and vascular reconstruction. However, the severely debilitated patient could not tolerate 2 simultaneous open procedures. She underwent emergent endovascular exclusion of the mycotic aneurysm with a stent-graft, followed immediately by laminectomy and stabilization of the thoracic spine. Intraoperative microbiology specimens showed no growth. The patient was maintained on prophylactic antibiotic therapy for 6 months. Fourteen months postoperatively, her neurologic function was near full recovery, and neither surveillance blood cultures nor radiologic examinations showed a recurrence of infection or aneurysm. Although the long-term outcome of endovascular stent-grafts in the treatment of culture-negative mycotic aneurysms is unknown, the use of these grafts in severely debilitated patients can reduce operative risk and enable recovery in the short term.