BACKGROUND: Molecular multitargeted small tyrosine kinase inhibitory (TKI) agents such as axitinib, sunitinib and pazopanib are commonly used in several types of solid tumors. Anemia is not a rare effect of these drugs which may occur at all grades. However, drug-induced immune hemolytic anemia (IHA), a very rare condition is distinctive from other types of anemia with its specific mechanism and management strategy.
METHODS: We reported three different TKI-induced IHA cases that occurred due to axitinib, sunitinib, and pazopanib, respectively. The first two cases were diagnosed with renal cell carcinoma and the last one was diagnosed with soft tissue sarcoma. They all presented with the characteristic symptoms of anemia and hemolysis. All the cases were detected positive for the complement C3d direct antiglobulin (direct coombs) test.
METHODS: Discontinuation of the causative drug and 1 mg/kg/day dose of corticosteroid treatment were able to control IHA in all three cases. Excluding the other factors of IHA and an evident laboratory and clinical benefit after withholding the TKI led to the diagnosis of TKI-related IHA in each case.
CONCLUSIONS: TKIs are relatively new in clinical practice and are being used for more indications and in more patients. To our knowledge#these three cases are unique in terms of axitinib#sunitinib#and pazopanib-related IHA.

BACKGROUND: Cold agglutinin disease (CAD) is a rare autoimmune hemolytic anemia mediated by immunoglobulin M autoantibodies that bind to the \"I\" antigen on erythrocytes. IgM binding results in either agglutination at ≤37°C, activation of the classical complement pathway, or both. Patients with CAD can have transient agglutination-mediated circulatory symptoms triggered by exposure to cold conditions. Separately, patients with CAD can experience complement-mediated symptoms such as anemia, hemolysis, and fatigue, but the effect of the season on these complement-mediated manifestations of CAD and clinical outcomes is not well understood.
METHODS: Using data from the Optum® de-identified Electronic Health Record dataset, we compared hemoglobin, markers of hemolysis (bilirubin and lactate dehydrogenase [LDH]), and healthcare resource utilization (HRU) between seasons for 594 patients (62% female; 66% aged ≥65 years) with CAD (defined as having CAD-related terms in their clinical notes on ≥3 separate occasions between December 2008 and May 2016). Laboratory parameters and HRU were compared between seasons using multivariate regression models.
RESULTS: Estimated median hemoglobin (9.87 g/dL in summer and 9.86 g/dL in winter; P = 0.944) and bilirubin (1.04 mg/dL in summer and 1.09 mg/dL in winter; P = 0.257) were similar in winter versus summer. While LDH was statistically significantly higher in winter compared with summer (P < 0.001), the estimated median value was above normal for both seasons (309 U/L in summer and 367 U/L in winter). HRU measures and transfusion and thromboembolism rates were similar across seasons.
CONCLUSIONS: Patients with CAD had evidence of persistent chronic hemolysis, HRU, and thromboembolism risk year round.

OBJECTIVE: Testing for drug-dependent antibodies is traditionally performed with the tube method either with drug-treated red blood cells or with untreated red blood cells in the presence of soluble drug. Gel microcolumn agglutination method was compared to tube testing for the demonstration of drug-dependent antibodies in the presence of soluble drug.
METHODS: Patient\'s samples were tested in parallel by tube and gel microcolumn agglutination method with untreated and/or enzyme-treated red blood cells in the presence of soluble drug.
RESULTS: Twenty six different patient\'s samples were studied and thirty nine tests performed to investigate antibodies directed against fifteen different drugs. There was a good correlation between the results obtained by tube and gel method in terms of analytical sensitivity and specificity. Reactions appeared to be stronger with the gel test than seen with the conventional tube method for most of the drug antibodies investigated. Enzyme-treated cells should be used in addition to untreated cells to improve the sensitivity of the method for detecting drug-dependent antibodies especially those directed against drugs that do not bind firmly to red blood cells.
CONCLUSIONS: Gel method appeared to be sensitive, reliable, reproducible, and comparable to the conventional tube method for the detection of all the drug-dependent antibodies investigated in this study. Further studies need to be performed to evaluate gel testing for the detection of drug-dependent antibodies that only react with drug-treated red blood cells.

We have reviewed the literature to identify and characterize reports of warm-antibody type, autoimmune hemolytic anemia in which the standard direct antiglobulin reaction was negative but a confirmatory test indicated that the red cells were opsonized with antibody. Three principal reasons account for the absence of a positive direct antiglobulin test in these cases: a) IgG sensitization below the threshold of detection by the commercial antiglobulin reagent, b) low affinity IgG, removed by preparatory washes not conducted at 4°C or at low ionic strength, and c) red cell sensitization by IgA alone, or rarely (monomeric) IgM alone, but not accompanied by complement fixation, and thus not detectable by a commercial antiglobulin reagent that contains anti-IgG and anti-C3. In cases in which the phenotype is compatible with warm-antibody type, autoimmune hemolytic anemia and the direct antiglobulin test is negative, an alternative method to detect low levels of IgG sensitization, use of 4°C, low ionic strength washes to prepare the cells for the direct antiglobulin test reaction to permit retention and identification of low affinity IgG antibodies, and, if the latter are uninformative, testing for sensitization with an anti-IgA, and, if necessary, an anti-IgM reagent identifies cases of warm-antibody type, immune hemolysis not verified by a commercial reagent.