Refractory asthma treatment is complicated by tracheobronchomalacia: case reports and review of the literature

A case report a delayed diagnosis of tracheomalacia resulting in prolonged steroid therapy, repeated hospital admissions and CT scans

A 30-year-old patient was admitted with shortness of breath and cough. Previous electronic entries state a history of asthma and hay fever. Repeated clerking by junior doctor states admission for treatment of likely exacerbation of asthma. The patient failed to fully improve with repeated courses of oral corticosteroids, regular nebulisers and oral antibiotics. The patient failed to improve even after several repeated admissions for similar admissions. On each admission she was subjected to CT scan and steroid courses, and at one point even had the authenticity of her symptoms questioned. Eventually she was found to have a case of tracheomalacia. Unfortunately, despite the eventual diagnosis, the patient has suffered side effects due to the delayed diagnosis and repeated treatment courses.

Troglitazone, a PPAR-γ agonist, decreases LTC4 concentration in mononuclear cells in patients with asthma

BACKGROUND

Asthma is an inflammatory disorder with multiple mediators involved in the inflammatory response. Despite several attempts, no new anti-inflammatory drugs have been registered for asthma treatment for several years. However, thiazolidinediones, peroxisome proliferator-activated receptor agonists, have demonstrated some anti-inflammatory properties in various experimental settings. The aim of this study was to assess the influence of troglitazone on LTC₄ and 15-HETE concentrations. It also evaluates TNF-induced eotaxin synthesis in peripheral blood mononuclear cells from 14 patients with mild asthma and 13 healthy controls.

METHODS

PBMCs were isolated from the whole blood of the asthmatics and healthy subjects and pretreated with 0.1, 1 or 10μM of Troglitazone. The cells were then exposed to 10^-6M calcium jonophore or 10ng/ml TNF. The production and release of LTC₄, 15-HETE and eotaxin were then assessed.

RESULTS

Troglitazone caused a dose-dependent inhibition in LTC₄ synthesis in both asthmatics and healthy subjects. Troglitazone did not influence 15-HETE or eotaxin production in either asthmatic patients or in healthy individuals.

CONCLUSION

Due to its inhibition of LTC₄ synthesis, troglitazone therapy is an interesting potential therapeutic approach in asthma and other LTC₄ related inflammatory disorders.

Flat trachea syndrome: a rare condition with symptoms similar to obstructive airway disease

Flat trachea syndrome, commonly known as 'tracheobronchomalacia', is a central airway disease characterised by excessive expiratory collapse of the tracheobronchial posterior membrane due to weakness in the airway walls. Patients present with symptoms such as chronic cough, dyspnoea and recurrent respiratory tract infections, which are often attributed to more common conditions such as asthma and chronic obstructive pulmonary disease (COPD). The term 'Flat Trachea Syndrome' was first proposed by Niranjan and Marzouk in 2010 following a retrospective study of 28 patients with the condition who underwent surgery for it. The authors advocated the term due to the primary abnormality being collapse of the posterior membranous wall of the central airways as opposed to softening of the tracheal cartilage (tracheobronchomalacia), which they proposed is a misnomer. We present a rare case of a patient with flat trachea syndrome on a history of COPD who initially presented with recurrent respiratory tract infections.