Thrombotic microangiopathy in cancer

Schistocyte detection in artificial intelligence age

Schistocytes are fragmented red blood cells produced as a result of mechanical damage to erythrocytes, usually due to microangiopathic thrombotic diseases or mechanical factors. The early laboratory detection of schistocytes has a critical impact on the timely diagnosis, effective treatment, and positive prognosis of diseases such as thrombocytopenic purpura and hemolytic uremic syndrome. Due to the rapid development of science and technology, laboratory hematology has also advanced. The accuracy and efficiency of tests performed by fully automated hematology analyzers and fully automated morphology analyzers have been considerably improved. In recent years, substantial improvements in computing power and machine learning (ML) algorithm development have dramatically extended the limits of the potential of autonomous machines. The rapid development of machine learning and artificial intelligence (AI) has led to the iteration and upgrade of automated detection of schistocytes. However, along with significantly facilitated operation processes, AI has brought challenges. This review summarizes the progress in laboratory schistocyte detection, the relationship between schistocytes and clinical diseases, and the progress of AI in the detection of schistocytes. In addition, current challenges and possible solutions are discussed, as well as the great potential of AI techniques for schistocyte testing in peripheral blood.

Onconephrology: Update in Anticancer Drug-Related Nephrotoxicity

The relation that connects cancer and renal damage is bidirectional and this renal damage worsens quality of life and increases morbidity in high-complexity patients such as patients with cancer and kidney injury. Strikingly, in the last decade, the treatment of advanced cancer has clearly advanced in terms of new therapeutic strategies with the ability to transform the advanced metastatic cancer in a chronic condition. In this new era of cancer therapies, cancer treatment including conventional chemotherapy, targeted cancer agents and immunotherapies among others are significantly associated with kidney injury. Renal toxicity that is currently seen in onconephrology departments is in part related to the new therapies such as immunotherapy, and to the prolonged survival achieved at the expense of increasing therapy lines, and a combination of different drugs. In this review, we will discuss in a practical way, nephrotoxicity caused by the main oncospecific treatments such as classical chemotherapy agents, targeted therapies, and immunotherapy. In addition, strategies for prevention and management recommendations in patients with malignancies and kidney disease will also be addressed.

Successful treatment in one myelodysplastic syndrome patient with primary thrombocytopenia and secondary deep vein thrombosis: A case report

BACKGROUND

The contradictory process of coagulation and anticoagulation maintains normal physiological function, and platelets (PLTs) play a key role in hemostasis and bleeding. When severe thrombocytopenia and deep vein thrombosis (DVT) occur simultaneously, the physician will be confronted with a great challenge, especially when interventional thrombectomy fails.

CASE SUMMARY

We describe a 52-year-old woman who suffered from myelodysplastic syndrome with severe thrombocytopenia and protein S deficiency with right lower extremity DVT. In this patient, the treatment of DVT was associated with numerous contradictions due to severe thrombocytopenia, especially when interventional thrombectomy was not successful. Fortunately, fondaparinux sodium effectively alleviated the thrombus status of the patient and gradually decreased the D-dimer level. In addition, no increase in bleeding was noted. The application of eltrombopag stimulated the maturation and differentiation of megakaryocytes and increased the peripheral blood PLT count. The clinical symptoms of DVT in the right lower extremities in this patient significantly improved. The patient resumed daily life activities, and the treatment effects were independent of PLT transfusion.

CONCLUSION

This is a contradictory and complex case, and fondaparinux sodium and eltrombopag may represent a good choice for the treatment of DVT in patients with severe thrombocytopenia.

Atypical Hemolytic Uremic Syndrome in a Patient With Metastatic Peritoneal Serous Carcinoma: A Case Report

Atypical hemolytic uremic syndrome (HUS) is a part of a large category of diseases known as thrombotic microangiopathies that present with hemolytic anemia, thrombocytopenia, and target organ damage mostly characterized by acute kidney injury. It is a rare and challenging diagnosis due to the complex pathophysiology underlying the disease and its overlap with other conditions. We report the case of atypical hemolytic uremic syndrome in a 61-year-old female with a history of metastatic peritoneal serous carcinoma of the ovary presenting with anemia and acute renal failure. 

The Link Between Conventional and Novel Anti-Cancer Therapeutics with Thrombotic Microangiopathy

BACKGROUND

Kidney disease associated with cancer and anti-cancer therapies has been increasingly recognized in the field of onco-nephrology. In particular, drug-induced nephrotoxicity has important implications since most chemotherapeutic agents have a nephrotoxic potential. Also, standard creatinine clearance methods used for the measurement of kidney function have been questioned in cancer patients due to factors like low muscle mass and poor nutritional status. Overestimations of the glomerular filtration rate, not only can increase the nephrotoxic potential of different agents, but also further limit the use of first-line therapies.

OBJECTIVE

This review covers specifically the drug-induced thrombotic microangiopathy and its two pathophysiologic mechanisms which include immune or idiosyncratic reactions, and non-immune or dose-dependent ones.

CONCLUSION

As novel cancer therapies are developed, it is paramount to pursue a better understanding of conventional and novel chemotherapeutic agents and their role in kidney disease.

TAFRO Syndrome with Renal Thrombotic Microangiopathy: Insights into the Molecular Mechanism and Treatment Opportunities

TAFRO syndrome is an extremely rare form of idiopathic MCD, characterized by thrombocytopenia, anasarca, fever, reticulin fibrosis on bone marrow biopsy, and organomegaly. Like idiopathic MCD, renal involvement is also a common presentation in patients with TAFRO syndrome. Furthermore, membranoproliferative glomerulonephritis (MPGN)-like injury and thrombotic microangiopathy (TMA) are the most reported histopathologic findings of renal biopsy. Several molecular mechanisms have been previously postulated in order to explain the TAFRO syndrome symptoms, including abnormal production of interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), etc. The role of these cytokines in renal injury, however, is not well understood. The aim of this review article is to summarize the latest knowledge of molecular mechanisms behind the TAFRO syndrome and their potential role in renal damage.

Thrombotic Microangiopathy in a Patient With COVID-19 Infection and Metastatic Cholangiocarcinoma

This is a case report of a 63-year-old African American female with a past medical history most significant for metastatic cholangiocarcinoma that presented for evaluation of persistent shortness of breath. Initial workup was remarkable for refractory anemia, moderate schistocytes on peripheral smear and lab work suggestive of a hemolytic anemia. Due to concern for thrombotic thrombocytopenic purpura (TTP), she subsequently underwent several rounds of plasma exchange without significant improvement. Secondary to progressive renal failure, patient eventually had a renal biopsy with findings remarkable for thrombotic microangiopathy (TMA). Simultaneously, patient was also diagnosed with coronavirus disease 2019 (COVID-19) infection. After a few weeks of supportive care, she was stable for discharge. Unfortunately, she did become dialysis dependent. Prior to hospital admission, she was being treated for metastatic cholangiocarcinoma and had received chemotherapy with gemcitabine. Her last chemotherapy session was approximately 3 weeks prior to her first hospitalization. Furthermore, although her hemolytic work did suggest TMA, it was not consistent with the diagnosis of TTP. She was transferred to a tertiary care center where hemolytic labs were trended, and supportive care was maximized. In light of the current COVID-19 pandemic, it is crucial to further investigate the pathophysiology of TMA in patients with active malignancies and COVID-19 infections. To our knowledge, this is the first case of TMA in a patient with both metastatic cholangiocarcinoma and COVID-19 infection.

Onconephrology: The intersections between the kidney and cancer

Onconephrology is a new subspecialty of nephrology that recognizes the important intersections of kidney disease with cancer. This intersection takes many forms and includes drug-induced nephrotoxicity, electrolyte disorders, paraneoplastic glomerulonephritis, and the interactions of chronic kidney disease with cancer. Data clearly demonstrate that, when patients with cancer develop acute or chronic kidney disease, outcomes are inferior, and the promise of curative therapeutic regimens is lessened. This highlights the imperative for collaborative care between oncologists and nephrologists in recognizing and treating kidney disease in patients with cancer. In response to this need, specific training programs in onconephrology as well as dedicated onconephrology clinics have appeared. This comprehensive review covers many of the critical topics in onconephrology, with a focus on acute kidney injury, chronic kidney disease, drug-induced nephrotoxicity, kidney disease in stem cell transplantation, and electrolyte disorders in patients with cancer.

Plasma exchange and thrombotic microangiopathies: From pathophysiology to clinical practice

Thrombotic microangiopathy (TMA) brings together many diseases that have a commonality in the apparition of mechanical hemolysis with consuming thrombopenia. In all cases, these diseases can be life threatening, thereby justifying the implementation of treatment as an emergency. First-line treatment represents plasma exchange. This treatment has proven efficiency in improving the vital patient's and functional prognosis. However, the administration methods of plasma exchange can be redefined in light of the understanding of the pathophysiology of TMA. The aim of this review is to try to define, from pathophysiology, the place of plasma exchanges in the modern therapeutic arsenal of TMA.

Intrapatient variability in concentration/dose ratio of tacrolimus predicts transplant-associated thrombotic microangiopathy

Tacrolimus (TAC) is essential for prophylaxis of acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic cell transplantation (allo-HSCT). We have sometimes observed large fluctuations in TAC concentration. However, links between the variability in the concentration or the concentration/dose (C/D) ratio of TAC and clinical complications remain ambiguous. To clarify relationships between various parameters of TAC and early complications such as pre-engraftment immune reactions/engraftment syndrome, aGVHD, and transplant-associated thrombotic microangiopathy (TA-TMA), a total of 146 patients who underwent allo-HSCT were included. Intrapatient variabilities in the concentration and C/D ratio of TAC were estimated by intrapatient mean absolute deviation (iMAD). The mean concentration and C/D ratio of TAC were not significantly different between with and without complications. A strong association was observed between greater iMAD for TAC C/D ratio from days 15 to 21 and the development of TA-TMA. iMAD values for TAC C/D ratio of 11.4 or greater was a risk factor for TA-TMA and the cumulative incidence of nonrelapse mortality (NRM) was significantly higher in patients with iMAD values for TAC C/D ratio of 11.4 or greater. Intrapatient variability in the C/D ratio of TAC was associated with the incidence of TA-TMA and NRM and might be useful for predicting TA-TMA.

Does Outcome/Survival of Patients With Myelodysplastic Syndromes Should Be Predicted by Reduced Levels of ADAMTS-13? Results From a Pilot Study

INTRODUCTION

Von Willebrand factor (vWF) cleaving protease ADAMTS-13 has a key role for maintaining normal size of vWF. A deficiency or dysfunction of vWF cleaving protease is associated with ultra large vWF multimers and thrombotic microangiopathy. Patients with cancers have reduced levels of vWF cleaving protease. In this pilot study, we have evaluated whether or not deficiencies of ADAMTS-13 were present in myelodysplastic syndromes (MDS). Moreover, we assessed if a reduction in basal levels of ADAMTS-13 may play a role in the prognosis of MDS.

PATIENTS AND METHODS

We measured and compared the levels of vWF cleaving protease ADAMTS-13 in 100 patients with MDS and 35 healthy controls. Patients were divided into 2 groups according to the International Prognostic Scoring System: group I consisting of 44 patients with low-risk MDS and group II of 56 patients with high-risk MDS. Patients with high-risk and low-risk MDS presented significantly lower levels of ADAMTS-13 than controls (P < .001 and P = .0177, respectively). High-risk patients had significantly lower levels of ADAMTS-13 when compared with the low-risk group (P < .001).

RESULTS

We found that reduced levels of ADAMTS-13 have a relationship with overall survival (P < .001). Statistical analysis showed that ADAMTS-13 correlates with cytogenetics (P < .001) and a tendency of slight correlation with platelet count and basal levels of ADAMTS-13 (R, 0.35; P value, 0.001). Moreover, we found that levels of ADAMTS-13 have correlation with response to treatment (P < .001).

CONCLUSIONS

ADAMTS-13 in MDS might represent a surrogate marker of prognosis, response to therapy, or disease progression. Further studies are needed.