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Biomedical subjects

Phuong-Thu T Pham

Publications and source records attributed to Phuong-Thu T Pham.

9 recordsLinked to original sources

Concurrent FSGS and Hodgkin's lymphoma: case report and literature review on the link between nephrotic glomerulopathies and hematological malignancies.

BACKGROUND: The link between the nephrotic syndrome (NS) and malignancy was first described in 1922. In solid tumors, the NS is most often due to membranous glomerulonephropathy, whereas in common hematological malignancies, minimal-change disease predominates. Focal segmental glomerulosclerosis (FSGS) is among the least frequently reported renal lesion associated with malignancy. METHODS: We report a case of the simultaneous diagnoses of FSGS and Hodgkin's lymphoma, and review the literature on various nephrotic glomerulonephropathies associated with common leukemia and lymphoma. RESULTS: Although nephrotic glomerulonephropathies rarely occur in association with acute leukemia, they have often been described in chronic lymphocytic leukemia (CLL). Membranoproliferative glomerulonephropathy and membranous glomerulonephropathy are the most common lesions observed in CLL. Nephrotic glomerulonephropathies have also been well documented among patients with lymphomas, in particular, Hodgkin's lymphoma. While minimal-change disease is most commonly found in association with Hodgkin's lymphoma, more diverse and complex renal lesions are associated with non-Hodgkin's lymphoma. FSGS remains a rare association with hematological malignancies. CONCLUSIONS: Nephrotic glomerulonephropathies are not only linked to solid-organ tumors, but also to hematological malignancies. A thorough evaluation, including a physical examination for lymphadenopathy and organomegaly, as well as a hematological evaluation, must be performed in all patients presenting with nephrotic glomerulonephropathies.

Adult↗

Noninvasive diagnosis of cellular and antibody-mediated rejection by perforin and granzyme B in renal allografts.

A major milestone in transplantation would be the use of biomarkers to monitor rejection. We examined the association between perforin and granzyme-B gene expression detected in the peripheral blood of renal allograft recipients with cellular and antibody-mediated rejection. Furthermore, we judged the appropriateness of assigning negative rejection statuses to persons without a biopsy whose grafts were functioning well clinically. Of the 46 patients who completed the study, recipients with cellular rejection had higher perforin and granzyme-B levels compared with nonrejectors (p = 0.006). Interestingly, recipients with antibody-mediated rejection also had higher perforin and granzyme-B levels compared with nonrejectors (p = 0.04). Patients with high levels of granzyme B had a probability of rejecting that was 26.7 times greater than those patients with low levels of granzyme B. Perforin and granzyme B had sensitivities of 50% and specificities of 95% in predicting rejection (cutoff value = 140). Assigning negative rejection statuses to recipients without a biopsy whose grafts were functioning well did not have a major effect on the direction or significance of covariate values. This study suggests that perforin and granzyme-B gene expressions in peripheral blood are accurate in detecting both cellular and antibody-mediated rejection.

Adult↗

Vasopressin excess and hyponatremia.

Hyponatremia is a common electrolyte disorder that frequently is overlooked and undertreated. Although the pathophysiological process of hyponatremia is complex, arginine vasopressin (AVP) is a common etiologic factor. Excess AVP release by osmotic or nonosmotic stimuli or both can lead to sodium and water imbalance. Conventional treatment options for hyponatremia, including water restriction and administration of sodium chloride with or without loop diuretics, do not directly address the underlying water retention induced by excess AVP in many cases. Clinical trials showed that AVP-receptor antagonists, including lixivaptan, tolvaptan, and conivaptan, produce aquaresis, the electrolyte-sparing excretion of free water, to correct serum sodium concentration. We review results from recent clinical trials involving AVP-receptor antagonists in the treatment of hyponatremia associated with AVP excess.

Arginine Vasopressin↗

Development of posttransplant antidonor HLA antibodies is associated with acute humoral rejection and early graft dysfunction.

BACKGROUND: The goal of this study was to determine whether the production of posttransplant antibodies directed against donor HLA mismatches (donor specific antibody; DSA) is associated with renal allograft rejection and early graft dysfunction. METHODS: Forty-nine adult renal allograft recipients with increased risk of rejection were enrolled during the period of October 2001 through May 2003 and were prospectively monitored for the development of anti-HLA antibodies. RESULTS: Of 49 patients, eight (16.3 %) patients were diagnosed with acute humoral rejection (AHR) and 11/49 (22.4%) patients were diagnosed with acute cellular rejection (ACR). A strong association between pretransplant HLA sensitization and AHR was found (P=0.005). Of the eight patients diagnosed with AHR, the majority developed DSA before or concomitant with episodes of rejection (P<0.001). Only 3 of 41 patients (7.3%) without AHR developed DSA. The pathogenic role of alloantibodies was further substantiated by analyzing their association with graft function as measured by serum creatinine levels. The average serum creatinine after the third month posttransplantation in DSA producers was 2.24+/-1.01 mg/dL, while in non-DSA patients the average serum creatinine was 1.41+/-0.37 mg/dL (P<0.01). CONCLUSION: This study reveals a strong association between the production of DSA, AHR, and early graft dysfunction. Our findings indicate that prospective monitoring for anti-HLA antibodies following transplantation is a useful test for the diagnosis and classification of AHR for identifying patients at risk of early graft dysfunction.

Acute Disease↗

Predictors and risk factors for recurrent scleroderma renal crisis in the kidney allograft: case report and review of the literature.

Scleroderma renal crisis (SRC) can lead to end-stage renal disease (ESRD) and subsequent need for dialysis and/or renal transplantation. We review all reported cases of renal transplantations in scleroderma patients from PubMed search, present UNOS data on transplant outcomes, and identify predictors for allograft SRC. Of the five cases with recurrent SRC, all developed ESRD within a year of onset of native kidney SRC, whereas none of those who developed ESRD more than 1-2 years after the onset of SRC developed recurrence. Anemia preceded allograft SRC in two cases, pericardial effusion in one, and skin tightening in two others. UNOS data (October 1987-July 2004) documented 260 transplants performed for the renal diagnosis of scleroderma, with a 5-year graft survival rate of 56.7%. The risk for allograft SRC recurrence appears to correlate with early native renal function loss following the onset of SRC. Recurrent SRC in the allograft may be heralded by multiple clinical markers known to be predictive of severe scleroderma, including progression of diffuse skin thickening, new-onset anemia and cardiac complications.

Anemia↗

Sirolimus-associated pulmonary toxicity.

BACKGROUND: Pulmonary toxicity has recently been recognized as a potentially serious complication associated with sirolimus therapy. We further detail this condition on the basis of our own cases and those reported in the literature. METHODS: We report three cases of suspected sirolimus-induced pulmonary toxicity that occurred in three renal transplant recipients and searched PubMed for all previously reported cases. RESULTS: Including our current cases, 43 patients with sirolimus-induced pulmonary toxicity have now been reported. Clinical data were incomplete in 28 cases. Analysis of available data for 15 patients revealed that the most commonly presenting symptoms were dyspnea on exertion and dry cough followed by fatigue and fever. Chest radiographs and high-resolution computed tomography scans commonly revealed bilateral patchy or diffuse alveolo-interstitial infiltrates. Bronchoalveolar fluid analysis and lung biopsy in selected case reports revealed several distinct histologic features, including lymphocytic alveolitis, lymphocytic interstitial pneumonitis, bronchoalveolar obliterans organizing pneumonia, focal fibrosis, pulmonary alveolar hemorrhage, or a combination thereof. The diagnosis of sirolimus-associated pulmonary toxicity was made after an exhaustive work-up to exclude infectious causes and other pulmonary disease. Sirolimus discontinuation or dose reduction resulted in clinical and radiologic improvement in all 15 patients within 3 weeks. CONCLUSION: The temporal relationship between sirolimus exposure and onset of pulmonary symptoms in the absence of infectious causes and other alternative pulmonary disease and the associated clinical and radiologic improvement after its cessation suggests a causal relationship. Because the use of sirolimus in organ transplantation has become more widespread, clinicians must remain vigilant to its potential pulmonary complication.

Adult↗

Inhibitors of ADAMTS13: a potential factor in the cause of thrombotic microangiopathy in a renal allograft recipient.

BACKGROUND: Thrombotic microangiopathy (TMA) is a well-known complication after renal allograft transplantation. In most cases, calcineurin inhibitor is believed to play a role in the development of this disorder. Recent studies have shown that a deficiency in the activity of the von Willebrand factor-cleaving metalloprotease ADAMTS13 causes thrombotic thrombocytopenic purpura. A similar mechanism occurring in patients who develop TMA after renal transplantation has not been described. METHODS: Analysis of plasma samples from a patient who developed TMA after receiving a cadaveric renal allograft revealed undetectable ADAMTS13 activity and the presence of its inhibitors. RESULTS: Discontinuation of cyclosporine and daily plasma exchange increased the ADAMTS13 activity, which was followed by resolution of the microangiopathic hemolysis and improvement of the graft function. At 3-month follow-up, the ADAMTS13 activity remained in the normal range and no inhibitors were detected. CONCLUSIONS: This is the first case to demonstrate a correlation between the presence of ADAMTS13 inhibitors and transplant-associated TMA. Autoimmune inhibitors of ADAMTS13 should be considered in patients with transplant-associated thrombotic microangiopathy. The role of calcineurin inhibitor in the formation of autoantibodies to ADAMTS13 remains to be explored.

Cyclosporine↗

Kidney transplantation at UCLA.

The demand for renal transplantation continues to increase. Combined organ transplantation currently accounts for approximately 10% of the kidney transplants at UCLA. As the demand for renal transplantation has increased, living kidney donation has become more common and achieves excellent results. Thirty-five percent of the 1,307 renal transplants at UCLA during the past 5 years were from living donors. The donor morbidity has been reduced with improvements in postoperative analgesia and laparoscopic nephrectomy techniques. Management of the patients waiting for cadaveric renal transplantation is becoming increasingly complex, since this population now exceeds 1,000 patients and the median waiting time is approaching 5 years. Improved immunosuppressive, antibiotic, and antiviral medications have significantly reduced the rate of acute rejection and serious infections. As long-term graft survival improves, the side effect profiles of newer medications are increasingly important. The one- and 3-year graft survival rates during the past 5 years were 98% and 90% for adult recipients of living donor kidneys and were 91% and 82% for recipients of cadaveric grafts, respectively. The results for pediatric transplants were 100% and 97% for living donor kidneys and 97% and 85% for cadaveric grafts at one and 3 years, respectively. We are pleased with our excellent results and the manner in which our program has responded to changes in the organ transplant environment.

Adult↗