Monoclonal gammopathy after liver transplantation: a risk factor for long-term medical complications other than malignancies

The Evolution of Monoclonal Gammopathy of Undetermined Significance in Kidney Transplant Recipients

It is unclear if immunosuppression increases the likelihood of malignant transformation of monoclonal gammopathy of undetermined significance (MGUS) and whether adverse renal outcomes in kidney transplant recipients with MGUS are more frequent.

Immunoglobulin abnormalities in 1677 solid organ transplant recipients. Implications for posttransplantation follow-up

BACKGROUND

Posttransplant lymphoproliferative disorder (PTLD) is a severe complication of solid organ transplantation (SOT). However, there is no consensus on PTLD screening methods. Gammopathies (GP), which occur in 10-25% of SOT recipients, have been linked to subsequent development of PTLD. Therefore, GP detection methods, such as serum protein electrophoresis (SPE), serum protein immunofixation (SIFE), urine protein immunofixation (UIFE) and the quantitative measurement of serum free light chains (SFLC) are candidate methods for PTLD screening.

OBJECTIVE

We aimed to assess the frequency of PTLD and GP, association of GP with subsequent PTLD, allograft loss or death and the diagnostic performance of SPE/SIFE in PTLD screening. The main objective was to explore, whether GP detection methods can be used to enhance the efficiency of PTLD screening and to formulate a concise algorithm for posttransplantation (post-Tx) follow-up.

METHODS

We performed a cohort study on 1677 SOT recipients with SPE/SIFE data who underwent kidney, liver, heart, pancreas, Langerhans islets or multiple organ transplantation at the Institute of Clinical and Experimental Medicine between 1966 and 2015. The median (IQR) of follow-up time was 8.0 (4.0-12.0) years.

RESULTS

The frequencies of PTLD and GP in SOT recipients were 2.8% and 6.4%, respectively. The frequencies of transient GP, GP of undetermined significance and malignant GP were 33%, 63% and 4% respectively. The median time between SOT and GP detection was 2.0 (interquartile range 1.0-7.0) years. GP was associated with a significantly higher risk of PTLD, allograft loss and death, with hazard ratios (95% confidence intervals) of a 6.06 (2.51-14.64), 2.61 (1.49-4.6) and 1.99 (1.2-3.3), respectively. Additionally, GP was associated with 2.98-fold increased risk of allograft loss in kidney transplant patients. SPE diagnostic sensitivity and specificity for PTLD were 14.8% and 93.9%, respectively. PTLD was diagnosed more often and earlier if SPE/SIFE was included in the post-Tx follow-up.

CONCLUSIONS

GP after SOT is associated with a high risk of PTLD, allograft loss and poor survival. The combination of SPE, SIFE, SFLC and UIFE is optimal for GP detection. These methods aid in identifying patients who are at risk for PTLD or allograft damage and should be included in regular post-Tx follow-up.

Monoclonal Gammopathy in HIV-1-Infected Patients: Factors Associated With Disappearance Under Long-Term Antiretroviral Therapy

OBJECTIVE

Monoclonal gammopathies (MGs) associated with HIV infection are frequent but their evolution and significance are uncertain in this population at high risk of lymphoproliferative disorder. Our aim was to describe the long-term evolution of MG in HIV-infected subjects under antiretroviral therapy.

METHODS

Retrospective study of HIV-1-infected adults, with a monoclonal (M) protein detected by serum protein electrophoresis and confirmed by immunofixation. Logistic regression was used to analyze factors associated with peak disappearance.

RESULTS

Between September 1997 and November 2012, 1219 serum protein electrophoreses were performed on our HIV cohort, and 137 (11.3%) MGs were detected. Seventy-seven subjects met the inclusion criteria: 68% male, median age 41 years, 47% AIDS stage, median CD4 count 237 per cubic millimeter, 81% uncontrolled HIV infection with HIV viral load over 400 copies per milliliter, 32% chronic hepatitis C, and 9% chronic hepatitis B. Eighteen subjects were not included because of previous or concomitant hemopathy. With a median follow-up of 6.8 years (interquartile range, 3.9-9.1), 66.2% of subjects showed a peak disappearance. In multivariate analysis, MG disappearance was associated with HIV virologic control (odds ratio, 5.98; 95% confidence interval: 1.63 to 21.87; P = 0.007) and the absence of hepatitis C virus replication at the end of follow-up (odds ratio, 10.16; 95% confidence interval: 2.36 to 43.69; P = 0.002). One subject developed a myeloma 3 years after the diagnosis of an IgA kappa MG.

CONCLUSIONS

MG associated with HIV infection concerned a young population and had favorable evolution on antiretroviral therapy in most cases. M protein disappearance was associated with HIV virologic control and the absence of chronic hepatitis C virus.

Neoplastic and non-neoplastic complications of solid organ transplantation in patients with preexisting monoclonal gammopathy of undetermined significance

Monoclonal gammopathy of undetermined significance (MGUS) occurs in 3-7% of the elderly population, with higher prevalence in renal failure patients, and is associated with a 25-fold increased lifetime risk for plasma cell myeloma (PCM), also known as multiple myeloma. Using the California State Inpatient, Emergency Department, and Ambulatory Surgery Databases components of the Healthcare Cost and Utilization Project (HCUP), we sought to determine whether patients with MGUS who undergo solid organ allograft (n = 22,062) are at increased adjusted relative risk (aRR) for hematologic malignancy and other complications. Among solid organ transplant patients, patients with preexisting MGUS had higher aRR of PCM (aRR 19.46; 95% CI 7.05, 53.73; p < 0.001), venous thromboembolic events (aRR 1.66; 95% CI 1.15, 2.41; p = 0.007), and infection (aRR 1.24; 95% CI 1.06, 1.45; p = 0.007). However, when comparing MGUS patients with and without solid organ transplant, there was decreased aRR for PCM with transplant (aRR 0.34; 95% CI 0.13, 0.88; p = 0.027), and increased venous thromboembolic events (aRR 2.33; 95% CI 1.58, 3.44; p < 0.001) and infectious risks (aRR 1.44; 95% CI 1.23, 1.70; p < 0.001). While MGUS increased the risk of PCM overall following solid organ transplantation, there was lower risk of PCM development compared to MGUS patients who did not receive a transplant. MGUS should not preclude solid organ transplant.