Blood CD9+ B cell, a biomarker of bronchiolitis obliterans syndrome after lung transplantation

Bronchiolitis obliterans syndrome is the main limitation for long-term survival after lung transplantation. Some specific B cell populations are associated with long-term graft acceptance. We aimed to monitor the B cell profile during early development of bronchiolitis obliterans syndrome after lung transplantation. The B cell longitudinal profile was analyzed in peripheral blood mononuclear cells from patients with bronchiolitis obliterans syndrome and patients who remained stable over 3 years of follow-up. CD24^hi CD38^hi transitional B cells were increased in stable patients only, and reached a peak 24 months after transplantation, whereas they remained unchanged in patients who developed a bronchiolitis obliterans syndrome. These CD24^hi CD38^hi transitional B cells specifically secrete IL-10 and express CD9. Thus, patients with a total CD9⁺ B cell frequency below 6.6% displayed significantly higher incidence of bronchiolitis obliterans syndrome (AUC = 0.836, PPV = 0.75, NPV = 1). These data are the first to associate IL-10-secreting CD24^hi CD38^hi transitional B cells expressing CD9 with better allograft outcome in lung transplant recipients. CD9-expressing B cells appear as a contributor to a favorable environment essential for the maintenance of long-term stable graft function and as a new predictive biomarker of bronchiolitis obliterans syndrome-free survival.

[Mesenteric ischemia in hemodialyzed patients]

OBJECTIVES

Mesenteric ischemia is uncommon in the general population but is frequently encountered in chronic hemodialysis patients. We present here four cases which occurred in our unit within one year while only six cases had been observed in the preceding twenty years.

OBSERVATIONS

Four chronic hemodialysis patients (age: 57 to 76 years) with renal failure due to diffuse atheromatous disease, presented non-occlusive mesenteric ischemia. One patient died and one underwent resection of the colon. For the final two patients, prophylactic therapy was initiated.

DISCUSSION

Mesenteric ischemia is a severe condition which appears to occur more frequently in end-stage renal disease. In the chronic hemodialysis patient excessive ultrafiltration or a too rapid filtration rate can favor ischemia. Prophylactic measures must be taken at the first sign of ischemia, especially since clinical and biological features of mesenteric ischemia remain largely non-specific.

Relationship of omega-3 fatty acid supplementation to plasma lipid peroxidation in predialysis patients with hypertriglyceridaemia

OBJECTIVES

Since it has been suggested that omega-3 polyunsaturated fatty acids (PUFA) may be an efficient treatment for dyslipoproteinaemia and renal function in uraemic patients, this study was carried out to evaluate the potential adverse effects of polyunsaturated acids on lipid peroxidation in patients with chronic renal failure.

PATIENTS AND METHODS

Five uraemic predialysis patients with various renal diseases presenting progressive renal failure and moderate hypertriglyceridaemia (1.93 +/- 0.60 g/L) in comparison with the reference values of our laboratory (0.88 +/- 0.20 g/L) were given 6 g of fish oil per day for 6 months in the form of Maxepa capsules containing a low dose of tocopherol acetate (10.5 mg/day). During the treatment we investigated the effect (expected to be beneficial) of n-3 PUFA on triglyceride plasma levels and renal function. We also investigated the potential side effect of such a treatment on lipid peroxidation.

RESULTS

A moderate decrease of triglycerides early after the introduction of the treatment (1.93 +/- 0.6 g/L vs 1.33 +/- 0.58 g/L; 0 vs 0.5 months) was observed. In all patients, lipid peroxides measured as thiobarbituric acid reactants increased early after the introduction of the n-3 PUFA therapy (2.8 + 0.8 vs 3.76 +/- 0.15 mumol/L; 0 vs 0.5 months). Organic hyperoxides were significantly different in these patients compared with laboratory values, but they did not increase significantly during the treatment.

CONCLUSION

It must be noted that polyunsaturated fatty acids should be used with caution in predialysis patients.

[Diabetic glomerulopathy]

Detecting a microalbuminuria in a diabetic patient is enough to diagnose a diabetic glomerulopathy (which is more properly termed diabetic nephropathy). To appreciate exactly means to know what are the lesions of mesangium matrix and interstitial tissue; therefore, a renal biopsy is useful, (but needs to be examined by quantitative histo-morphometry). Numerous factors facilitate the progression of renal insufficiency in these patients: high blood pressure, poor glycemie control, high protein diet. Avoiding each of these factors allows to delay the time of dialysis and renal transplantation. Now diabetics represent the large group of patients in renal replacement therapy world-wide. These therapies are twice to thrice as expensive as they are for non diabetic patients.

[Mixed cryoglobulinemia with necrotizing angiitis. Apropos of 2 cases]

Out of a series of 26 personal cases, 2 cases of mixed IgM-IgG cryoglobulinemia, one type II the other type III, are reported because they were associated with histologically proven necrotizing vasculitis. In both cases the numerous symptoms were due to renal damage (the vasculitis was discovered in the kidney) and to peripheral neuropathy. One of the patients died; the other had severely deteriorated general condition and required substitution hemodialysis. Cases of vasculitis associated with mixed cryoglobulinemia have often been published, but there are few reports mentioning necrotizing vasculitis; a search in the literature yielded only 9 cases. This small number does not mean that mixed cryoglobulinemia should not be listed among the causes of necrotizing vasculitis, but it makes it difficult to extract those specific features that would enable to predict which case of mixed cryoglobulinemia is associated or not with necrotizing vasculitis.