In-vitro growth patterns of bone marrow erythroid progenitors from patients with post-renal transplant erythrocytosis

Background: Erythrocytosis is relatively common after renal transplantation and is associated with a higher risk of thromboembolism. Its aetiology is unclear and there is still debate about the most frequently suggested causes. The culture in vitro of erythroid progenitors is regarded as a useful tool for the differential diagnosis of patients with unclear erythrocytosis. We studied the growth in vitro of bone marrow erythroid progenitor from renal transplant patients with erythrocytosis and controls without erythrocytosis. Subjects and methods: Thirteen renal transplant patients with erythrocytosis and 12 normocythaemic renal transplant controls were studied. The clinical characteristics of these patients were evaluated and serum erythropoietin (Epo) and ferritin levels were determined. Bone marrow erythroid progenitors were cultured both with and without the addition of Epo to the medium. Results: Samples from six polycythaemic patients and seven controls did not grow spontaneously in the absence of exogenous Epo. Three cases of post-transplant erythrocytosis and five controls produced CFU-E, but not BFU-3. A few CFU-E and BFU-E grew spontaneously in samples from four polycythaemic patients but not in samples from the controls. Addition of 1 unit per millilitre Epo caused similar increases in the number of colonies in both polycythaemic patients and controls. Of the nine patients eligible for follow-up, all four with spontaneous growth of BFU-E had transient erythrocytosis and four of the five patients with no spontaneous growth or spontaneous growth of CFU-E only had persistent erythrocytosis requiring treatment with ACE inhibitors. Conclusions: Pathophysiology of post-transplant erythrocytes is heterogenous. In one-third of the patients, there was unexpected, spontaneous and transient growth of BFU-E which was not predictive of permanent erythrocytosis. The results of stem-cell studies suggest that in these cases erythrocytosis may be caused by defective regulation of erythroid progenitor proliferation, possibly due to particular cellular interactions or the effect of cyclosporin on erythropoiesis.     

Magnetic resonance imaging may be an asset to diagnose and classify fluoroquinolone-associated Achilles tendinitis

Summary— The aim of this study was to document the accuracy of magnetic resonance imaging (MRI) during fluoroquinolone- associated Achilles tendinitis. Fourteen Achilles tendons were examined by MRI (T1 and T2 or T2*-weighted sequences) in nine patients with typical tendinopathy (13 cases of tendinitis and 1 rupture) during fluoroquinolone therapy. Tendinous involvement was classified according to the prominence of intra- or peritendinous changes. The most typical feature was the presence of intratendinous changes, longitudinal or transversal, detected on T1 or T2-weighted sequences. Peritendinitis was most visible in two cases and nodular involvement in three cases. It was concluded that MRI appears a helpful and accurate method in identifying and classifying such iatrogenic tendinitis. In addition, MRI indicates orthopedic management when detecting risk of rupture.     

Treatment of end-stage renal failure after heart transplantation

Background: Five to 10% of heart-transplant recipients develop end-stage renal failure (ESRF). Little is known about the outcome of these patients under renal replacement therapy. Methods: We conducted a retrospective study in 16 men (mean age 52.8±7.4 years at heart transplantation) who developed ESRF 5.3±2.1 years later. Results: Haemodialysis (HD) was the first-line treatment (mean Kt/V 135±0.4). Vascular access was unsuccessful in six patients (37.5%) due to peripheral arteriopathy and they were treated with tunnelled catheters for an average 15 months without bacterial infection. Mean weight was 68.4±10 kg at onset of HD and 61.7±9 kg one month later. Despite this reduction in extracellular overload one antihypertensive drug was required in 75% of patients and two drugs in 12.5%. One patient tolerated automated peritoneal dialysis (PD) for 16 months (weekly Kt/V 2.1) despite persistent anuria. Renal transplantation (RT) was contraindicated in eight patients because of aortoliac arteriopathy (n=5), poor general status (n=2), or ischaemic heart disease (n=1). RT was performed in eight patients with no acute episode of heart or renal graft rejection. There were no serious infectious complications. Three months after RT, mean serum creatinine was 115 &mgr;mol/l. One patient developed post-transplant lymphoproliferative disorder 3.5 months after RT and was successfully treated with transplant nephrectomy. Sudden death occurred in two patients 18 and 33 months after RT. Overall patient survival was 100, 78, and 59%, 1, 2 and 3 years after HD onset respectively. Using a time-dependent variable, the Cox model analysis demonstrated that heart-transplant recipients with ESRF have a relative risk of death 3.2 times higher than those without ESRF (95% CI=1.3-7.8). Conclusions: HD, PD, and RT can be useful for the treatment of ESRF after heart transplantation. After initiating HD, patient survival is nearly the same as that reported in patients in Europe undergoing HD for other causes. But ESRF seems to reduce life expectancy in heart-transplant recipients.     

Elevated body lead burden from drinking water in end-stage chronic renal failure

Delta aminolaevulinic acid dehydratase (ALA-D) was assayed in66 patients with end-stage renal failure who live in a regionwhere there is a high risk of lead poisoning from drinking water(Vosges mountains). Sixty patients received dialysis and sixunderwent renal transplantation. Results were compared to thoseobtained in 366 control subjects with normal renal functionhospitalized in a department of Internal Medicine and livingin the same geographical area. The ALA-D level was significantlylower in dialysed patients (0.40±20) than in controls(0.57±0.31) (P = 0.0014). Transplant recipients had ALA-Dlevels comparable to subjects with normal renal function (0.59± 0.37). In this high-risk population an EDTA test wasperformed in 74 subjects (with normal renal function and 17dialysis patients in combination with haemofiltration for thelatter patients. In the two study groups a negative correlationwas found between ALA-D and the amount of lead che-lated duringthe 24 h following administration of EDTA (r= –0.77 and–0.88 respectively). In subjects who live in an area ofendemic lead poisoning, the incidence of elevated body leadburden from drinking water was similar in the group with normalrenal function and in the group of dialysed patients (18.6 and8.3% respectively). This study shows (i) that in dialysis patients, measurementof ALA-D represents an accurate screening test for lead overload,provided that the lower threshold of normal is lowered from0.40 to 0.20, and (ii) that diagnosis and treatment are possibleby administering EDTA in conjunction with haemofiltration orCAPD.