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We read with interest the case report by Ledsonet al 1 describing a non-cystic fibrosis individual with chronic Burkholderia cepacia bronchiectasis. Although B cepacia most commonly affects patients with cystic fibrosis, it is also known to infect patients with chronic ventilatory requirements or immunocompromised patients.2 The immunocompromised patient population who appear most vulnerable toB cepacia infection are those with chronic granulomatous disease where the defect in neutrophil burst3 predisposes them to infection by specific organisms. Although the patient described by Ledsonet al had normal immunoglobulins, we wonder whether she has a defect in either neutrophil burst or chemotaxis to explain her unusual complaint.
authors’ reply Drs Suresh and Doull suggest that the chronic B cepaciacolonisation of the respiratory tract in our patient may be due to a peculiar defect in her immune system, specifically an abnormality of neutrophil burst or chemotaxis. We presume they base this speculation on their experience of chronic granulomatous disease in children where acute infections with B cepacia have been described. However, our patient is a mature adult who has had an unremarkable past medical history with no evidence of recurrent childhood infections. She has never required ventilation and, despite exhaustive testing, we have been unable to demonstrate any defect in her immune system.
Furthermore, we have tested her neutrophil burst function (using the nitroblue tetrazolium slide test1-1) and found it to be normal. We have not assessed her neutrophil chemotaxis since this is not easily performed. However, such disorders of neutrophil function predispose to infections with catalase positive organisms and usually present at an early age with staphylococcal or fungal infections, particularly of the skin and lung.1-2 Our patient gives no such history and we are therefore confident that she does not have an abnormality of neutrophil chemotaxis.
We thank the authors for their comments and welcome any further suggestions that may throw light on the management of this difficult clinical problem.