Hemolytic anemia after kidney transplantation: a prospective analysis

Engineering Therapeutics to Detoxify Hemoglobin, Heme, and Iron

Hemolysis (i.e., red blood cell lysis) can increase circulatory levels of cell-free hemoglobin (Hb) and its degradation by-products, namely heme (h) and iron (Fe). Under homeostasis, minor increases in these three hemolytic by-products (Hb/h/Fe) are rapidly scavenged and cleared by natural plasma proteins. Under certain pathophysiological conditions, scavenging systems become overwhelmed, leading to the accumulation of Hb/h/Fe in the circulation. Unfortunately, these species cause various side effects such as vasoconstriction, hypertension, and oxidative organ damage. Therefore, various therapeutics strategies are in development, ranging from supplementation with depleted plasma scavenger proteins to engineered biomimetic protein constructs capable of scavenging multiple hemolytic species. In this review, we briefly describe hemolysis and the characteristics of the major plasma-derived protein scavengers of Hb/h/Fe. Finally, we present novel engineering approaches designed to address the toxicity of these hemolytic by-products.

Passenger lymphocyte syndrome after ABO-mismatched kidney transplantation: A case report and literature review

BACKGROUND

Passenger lymphocyte syndrome (PLS) is a rare post solid organ transplantation complication, usually occurring after ABO- or Rh-mismatched transplantation. In general, PLS can lead to severe hemolytic anemia, but it is usually a self-limited disease. Most PLS cases start with a decreased hemoglobin (Hb) level and require donor type RBC transfusion as the only treatment.

CASE REPORT

In our case, the allograft was given by an O-type Rh-D(+) donor and received by an A-type Rh-D(+) recipient. The PLS was developed on the post-operative day (POD) 10 with an increased indirect bilirubin (IDBIL) level as the first clinical symptom, while the Hb level did not significantly decrease. The PLS was diagnosed on POD 17 by a direct antiglobulin test (DAT) and a blood group test. The patient quickly became stable on POD 18 after a total of eight units of O-type RBC transfusion. Kidney function was uneventful in the entire PLS period.

CONCLUSION

In ABO-mismatched kidney transplantation, an increased level of IDBIL should be considered as the first symptom of PLS even without an Hb decrease. The kidney function may be not affected by the PLS symptoms.

Passenger lymphocyte syndrome in renal transplantation: A systematic review of published case reports

BACKGROUND

Passenger lymphocyte syndrome (PLS) is an immune-mediated hemolysis that occurs after ABO-mismatched kidney transplantation. PLS is caused by donor lymphocytes producing antibodies to recipient red blood cells, resulting in hemolysis. The incidence of PLS has been reported to be approximately 20% in patients with ABO-mismatched groups. Nevertheless, there is no comprehensive review of PLS following renal transplantation. In this review, we systematically summarized the data of patients with PLS after renal transplantation to help clinicians diagnose and treat more effectively.

METHODS

A systematic review was conducted using PubMed, Embase, and Web of Science. All relevant data were collected, including age, sex, and clinical and immune parameters.

RESULTS

A total of 91 published cases were identified. The age ranged from 9 to 70 years old and 58.2% were male. Eighty-six cases were only kidney transplantations, one was liver-kidney transplantation, three were pancreas-kidney transplantations, and one was intestinal-kidney transplantation. Of these cases, 27 received kidneys from deceased donors, whereas 40 received kidneys from living donors. Most patients showed immune hemolysis dominated by anaemia, which was significantly improved after symptomatic support treatment, such as blood transfusion and erythropoietin injection.

CONCLUSION

PLS is an immune-mediated disease that can occur in patients with ABO-mismatched renal transplantation, which commonly causes hemolysis, although death or deformities of the graft can also occur in patients with the disorder. Symptomatic supportive treatment is an effective treatment scheme at present, but more effective treatment and prevention schemes still need to be explored.

Passenger Lymphocyte Syndrome; a Review of the Diagnosis, Treatment, and Proposed Detection Protocol

Passenger lymphocyte syndrome (PLS) is caused by the transfer of B-lymphocytes present in the donor graft into the recipient circulation following solid organ or hematopoietic stem cell transplantation. These cells may produce antibodies against the recipient's red blood cells, thereby triggering antibody dependent cytotoxicity and erythroid clearance, with potential resulting hemolysis and jaundice. Although uncommon, the true incidence is unknown because many cases are subclinical, with only serologic findings or with non significant levels of hemolysis detectable clinically or by laboratory monitoring. Thus, these cases may not be detected in the immediate perioperative period. No standardized consensus exists on screening for PLS in patients. Through a review of the literature from 2009 to 2019, we aim to approximate the incidence of this condition in different solid organ transplant settings, as well as to streamline recognition, detection, and management of PLS early in the disease course to prevent adverse outcomes and minimize invasive therapy. The resultant literature review yielded 22 case reports and 8 case series comprising 71 solid organ transplant patients. Hematopoietic stem cell transplant cases were excluded, as PLS cases related to solid organ transplant were the primary focus of this review. Our institution has traditionally handled PLS on a case-by-case basis, although we hope to improve this process through an introduction of an algorithm based on review of the literature and formalized communication with primary caregivers.

Passenger Lymphocyte Syndrome After Pediatric Liver Transplantation

BACKGROUND

Passenger lymphocyte syndrome (PLS) is a less known etiology of acute onset anemia following ABO-compatible (ABO-c) liver transplantation (LT). Available literature on PLS after pediatric LT is limited. Therefore, we evaluated the prevalence, clinical course, and risk factors of PLS in children following ABO-c LT.

METHODS

A single-center retrospective review of all children who underwent LT between 2000 and 2017 was performed. PLS was defined as a drop-in hemoglobin >20 g/L within 30 days of LT, with positive direct antiglobulin test and 1 laboratory test confirming hemolysis. Chi square and student t tests compared variables between subjects with and without PLS.

RESULTS

Amongst 333 pediatric LT performed, 51 children received an ABO-c graft. PLS was diagnosed in 7 (14%) subjects at a median of 10 days after LT. There were no significant differences in patient demographics, graft type, or immunosuppression between those who did and did not develop PLS. Recipient blood group A+ receiving a donor O+ graft was a risk factor for PLS (P = 0.015). All PLS subjects recovered with blood transfusions (median 2), and no additional interventions. Three subjects initially received recipient (instead of donor) blood group red cells.

CONCLUSIONS

We report a 14% prevalence of PLS following pediatric ABO-c LT. Recipient blood group A+ receiving a donor O+ graft is a risk factor for PLS. Recognition of PLS as a cause of early acute anemia in pediatric ABO-c LT enables timely transfusion with donor (rather than recipient) blood group red cells.

Genetic testing to resolve the source of haemolytic antibody in solid organ transplantation

BACKGROUND

Antibody-mediated haemolysis due to passenger lymphocyte syndrome arising in the setting of solid organ transplant can be devastating. Some degree of passenger lymphocyte syndrome is said to occur in up to 10% of ABO mismatched renal transplants, 40% of ABO mismatched liver transplants, and 70% of ABO mismatched heart-lung transplants; a reflection of the number of memory B cells transplanted with the organ. Passenger lymphocyte syndrome is less common with minor red cell antigens but can still be severe.

MATERIALS AND METHODS

We review a series of patients who developed passenger lymphocyte syndrome after solid organ transplantation. Conventional serological testing was performed using tube and solid-phase testing. Molecular testing was performed using a gene-chip array.

RESULTS

In patients receiving a minor antigen mismatched organ transplant and multiple allogenic red cell transfusions, serological methods proved insufficient to resolve the source of minor blood group antibodies that arose in the aftermath of the transplant. Genetic testing was able to clearly resolve donor and recipient types.

DISCUSSION

Passenger lymphocyte syndrome after mismatched organ transplantation is not rare, but the syndrome associated with non-ABO antibodies occurs in a much smaller subset of these cases. The mixtures of organ donor, recipient, and other transfused red blood cells profoundly limit the usefulness of serological testing. Genetic assignment of minor blood types to donor and recipient can guide therapy and inform prognosis.

Antithymocyte globulin-induced hemolytic anemia and thrombocytopenia after kidney transplantation

Antithymocyte globulin is the most widely used lymphocyte-depleting treatment in kidney transplantation. In spite of the frequency of side effects, including anemia and thrombocytopenia, their pathophysiological mechanisms are not clearly established. Here, we report the case of a 21-year-old patient who had a first kidney transplantation and received induction immunosuppressive therapy by thymoglobulin. Immediately after kidney transplantation, he developed a severe hemolytic anemia and thrombocytopenia with a subsequent perirenal hematoma, which lead to a second surgical procedure and a transfer to the intensive care unit. Our patients' anemia and thrombocytopenia had heteroimmune characteristics, and thymoglobulin therapy was suspected to be the cause, via an interaction with a common Fc-receptor epitope in the different cell lines.

Nonhemolytic passenger lymphocyte syndrome

BACKGROUND

An 8-month-old recipient of a liver segment transplant had anti-D detected for the first time in her Day 5 posttransplant plasma and anti-C detected for the first time in her Day 55 posttransplant plasma. The donor's plasma contained anti-C and anti-D. Clinical and laboratory findings established a diagnosis of passenger lymphocyte syndrome (PLS). Hemolysis did not occur, because the recipient's blood group phenotype was, by chance, D- C-.

STUDY DESIGN AND METHODS

To evaluate contemporary practice for diagnosing PLS, we conducted a retrospective 10-year literature review.

RESULTS

There were 31 studies (63 cases) of PLS of which eight cases (four studies) were hematopoietic stem cell and 55 (27 studies) were organ transplants. All eight (100%) hematopoietic stem cell and 52 (95%) organ transplants were associated with hemolysis. Of the four studies of hematopoietic stem cell PLS, three actively screened for posttransplant blood group antibodies. Of 27 studies of organ PLS, one actively screened for antibodies. Antibody screens detected five cases of hematopoietic stem cell PLS before hemolysis was apparent and two cases of organ PLS with antibodies without hemolysis.

CONCLUSION

Focusing on hemolysis, without a comparable effort to detect donor-derived antibodies diverts from the primary pathophysiology of PLS and limits capturing the full scope of the syndrome. Recognition of hemolytic and nonhemolytic subcategories of PLS is recommended. When feasible, an antibody screen performed on the donor's plasma when collecting the hematopoietic stem cells or before an organ harvest could result in an alert that the donor has formed an alloantibody(s) and the recipient is a risk for PLS. Alternatively, a routine antibody screen performed on the recipient's plasma 1 week posttransplant and, if negative, repeated 3 to 5 weeks posttransplant would detect any donor-derived antibodies and improve alignment of clinical practice with the pathophysiology of PLS.

Passenger lymphocyte syndrome in ABO and Rhesus D minor mismatched liver and kidney transplantation: A prospective analysis

The increasing demand for solid organs has necessitated the use of ABO and Rhesus (Rh) D minor mismatched transplants. The passenger lymphocyte syndrome (PLS) occurs when donor lymphocytes produce antibodies that react with host red blood cell (RBC) antigens and result in hemolysis. Our aim was to evaluate prospectively the role of PLS in post transplant anemia and hemolysis in ABO and RhD minor mismatched recipients of liver and kidney grafts and to study the association of PLS with donor lymphocyte microchimerism. We examined 11 liver and 10 kidney recipients at Day +15 for anemia, markers of hemolysis, direct antiglobulin test and eluates, and serum RBC antibodies. Microchimerism was determined in peripheral blood lymphocytes by genotyping of simple sequence length polymorphisms encoding short tandem repeats. Immune hemolytic anemia and anti-recipient RBC antibodies were observed in 2 out of 11 liver (18.2%) and 2 out of 10 kidney (20%) transplants. RBC antibody specificity reflected the donor to recipient transplant, with anti-blood group B antibodies identified in 2 cases of O to B and 1 case of A to AB transplants while anti-D antibodies were detected in 1 case of RhD-negative to RhD-positive transplant. Donor microchimerism was found in only 1 patient. In conclusion, passenger lymphocyte mediated hemolysis is frequent in minor mismatched liver and kidney transplantation. Recognizing PLS as a potential cause of post transplant anemia may allow for early diagnosis and management to decrease the morbidity and mortality in some patients.

Blood disorders after kidney transplantation

Post transplant anemia (PTA) is a common issue in kidney transplant recipients. Most importantly it is associated with an impaired allograft function. Other important factors associated with PTA are immunosuppressive drugs (MPA, AZA and SRL), iron deficiency, infections (Parvo B19), older donor age, rejection episodes, an increased inflammatory state, and erythropoietin hyporesponsiveness. As there are no adequately powered RCTs in the kidney transplant population on anemia treatment with ESA, we have to rely on what we know from the large RCTs in the CKD population. The recently published KDIGO guidelines do not recommend treatment with ESA if Hb is >10 g/dl. Repletion of iron stores is emphasized. Post transplant leukopenia (PTL) and thrombocytopenia (PTT) are frequent complications especially in the first six months after kidney transplantation. Myelosuppression caused by immunosuppressive agents (MPA, AZA, SRL, rATG), antimicrobial drugs (VGCV), and CMV infection is the predominant cause. There are no widely accepted guidelines on treatment strategies, but most often dose reduction or discontinuation of causative medication is done. Most clinicians tend to decrease MPA dose, but this is eventually associated with an increase in acute rejection episodes. VGCV dose reduction (preemptive treatment instead of CMV prophylaxis) may be a successful strategy. In severe cases G-CSF treatment is an important management option and seems to be safe.