Simulated waiting list prioritization for equitable allocation of donor lungs.

BACKGROUND: In lung transplantation (LTx), allocation of donor lungs is usually based on blood group, height and waiting time. Long waiting times favor patients with a slowly progressive end-stage lung disease and make the current allocation system the subject of discussion. In an attempt to equalize the chances for transplantation for every patient, irrespective of diagnosis, we investigated the effect of diagnosis-dependent prioritization on the waiting list, using a simulation model. METHODS: For the main disease categories on the waiting list, the relative risks of dying while on the waiting list were calculated using empirical data from the Dutch LTx program gathered over a period of 10 years. In a microsimulation model of the Dutch LTx program based on data from the actual situation, patients with diagnoses associated with a statistically significant increased risk of death while on the waiting list were prioritized by multiplying the time on the waiting list by the relative risk. RESULTS: Relative risks of death on the waiting list were increased significantly in patients with cystic fibrosis, primary pulmonary hypertension and pulmonary fibrosis. Prioritization resulted in an increased chance of transplantation for the prioritized diagnoses and a decreased chance for the non-prioritized diagnoses. The distribution of diagnoses after LTx was almost equal to the distribution of diagnoses on the waiting list. CONCLUSION: The simulated method of prioritization on the waiting list is a step forward to a more equitable allocation of donor lungs. Moreover, this method is clinically feasible, as long as the waiting list is updated frequently.

Long-term survival despite early loss of graft function after single lung transplantation for pulmonary fibrosis.

We report a patient who received a single, left lung transplantation for idiopathic pulmonary fibrosis. The effect of the graft on pulmonary improvement was only temporary, because the patient developed obliterative bronchiolitis (OB), resulting in complete destruction of the graft. The patient, however, remains alive 6 years after OB was diagnosed, apparently as a consequence of native lung improvement with triple-immunosuppressive medicine. This case is of interest for several reasons: first, it shows that pulmonary fibrosis may respond to intensive immunosuppressive therapy; second, it demonstrates that ventilation scintigraphy is useful in addition to pulmonary function tests in estimating the actual function of the graft after single lung transplantation; and third, it appears that the gradation of bronchiolitis obliterans syndrome (BOS) after single lung transplantation may overestimate the true function of the transplant.

Size matching in lung transplantation using predicted total lung capacity.

Height is used in allocation of donor lungs as an indirect estimate of thoracic size. Total lung capacity (TLC), determined by both height and sex, could be a more accurate functional estimation of thoracic size. Size-matching criteria based on height versus predicted TLC was retrospectively evaluated, and, furthermore, whether a TLC mismatch was related to clinical and functional complications. The ratio of donor and recipient height, as well as the ratio of predicted TLC in donors and recipients, were calculated in 80 patients after bilateral lung transplantation. Complications evaluated included persistent atelectasis, persistent pneumothorax and increased number of days in intensive care, occurrence of bronchiolitis obliterans syndrome and limitation of exercise capacity. Median height donor/recipient ratio was 1.01 (0.93-1.12). Median predicted TLC donor/recipient ratio was 1.01 (with a clearly broader range 0.72-1.41). Neither sex mismatch nor TLC mismatch were related to clinical or functional complications. Allocation of donor lungs based upon height alone leads to a substantial mismatch in total lung capacity caused by sex mismatch. The absence of complications suggests that a greater height donor/recipient discrepancy can be accepted for allocation than previously assumed.

Visual symptoms after lung transplantation: a case of progressive multifocal leukoencephalopathy.

After solid organ transplantation, signs and symptoms of the central nervous system may present a diagnostic challenge. A 43-year-old patient developed a decrease in vision 15 months after bilateral lung transplantation. The initial diagnosis was a left posterior cataract, but left eye cataract extraction did not improve his vision. Seizures led to investigation of a broader differential diagnosis (cyclosporine intoxication, post-transplant lymphoproliferative disorder, infectious disease, chronic lymphatic leukemia). The clinical diagnosis of progressive multifocal leukoencephalopathy (PML) was confirmed by demonstration of JC virus in the cerebrospinal fluid and by autopsy findings. Modulation of the immunosuppressive regimen was unsuccessful. This case illustrates that decreased vision in immunocompromised patients may be the first manifestation of PML.