In hemodialysis using vascular catheters (VC), inadequate blood flow can lead to decreased dialysis efficiency due to increased re‒circulation rates and downtime caused by thrombosis or circuit occlusion. Therefore, appropriate VC tip positioning is critical to avoid VC‒related issues. However, quantitative studies evaluating the relationship between the VC tip position and blood flow characteristics are limited. In this study, we utilized records from 178 patients who received VC‒based hemodialysis conducted from 2019 to 2022 to evaluate the relationship between VC tip positioning and blood flow rates, dialysis efficiency, and safety, focusing on the internal jugular and femoral veins, respectively. Maximum effective blood flow rates were calculated by subtracting re‒circulation from maximum achievable blood flow rates. VC‒related problem rates were categorized into four stages and verified. As a result, positioning of the tip caudal to the carina in the internal jugular vein, and positioning it cranial to the Jacoby line in the femoral vein, were associated with high maximum effective blood flow rates and low rates of VC‒related problems. When performing dialysis using VC, placing the tip in these positions may lead to higher dialysis efficiency and potentially avoid VC‒related issues.
Haptoglobin (Hp) is required for the metabolism of hemoglobin into bilirubin after hemolysis. Herein, we report a case of thrombotic microangiopathy (TMA) in a person with permanently low expression of Hp. The patient was an 80‒year‒old man. He was referred to our hospital because of rapid deterioration of renal function within a few days. The patient had thrombocytopenia, anemia with schistocytes, elevated LDH, and his serum Hp level was below detection sensitivity. During the course of blood transfusion and hemodialysis as supportive care, TMA subsided. The patient was weaned from hemodialysis. Two years after discharge, plasma Hp concentration remained below the detection sensitivity of conventional nephelometry and was barely detectable by high‒sensitivity ELISA. The absence of jaundice during the acute phase of TMA was likely due to low Hp expression. When such an atypical sign is observed in TMA in the future, congenital Hp deficiency should be considered. Special precautions against anaphylaxis are recommended during transfusion and plasma exchange, which may become the preferred treatment options.
We report a case of toxic epidermal necrolysis (TEN) in a hemodialysis patient with acute myeloid leukemia (AML) that was treated successfully with multidisciplinary therapy. A 44‒year‒old man, who had been undergoing maintenance hemodialysis since the age of 38, was diagnosed with AML 4 months earlier. After diagnosis, he was treated with remission induction therapy and achieved remission. Thereafter, he underwent two monthly cycles of consolidation chemotherapy. He was subsequently re‒admitted to our hospital for a third round of consolidation chemotherapy. On the 12th day of hospitalization, he developed a high fever and general fatigue. He was diagnosed with febrile neutropenia due to chemotherapy. He was administered wide‒spectrum antibiotics; however, his fever did not improve. On the 14th day, antibiotics were changed, and intravenous immunoglobulin was administered. On the same day, the patient developed generalized erythema, blisters, and oral cavity erosions. Two days later, a diagnosis of TEN was made based on clinical findings and a skin biopsy that revealed necrosis across all layers of the epidermis. Steroid pulse therapy and plasma exchange (PE), performed three times in total, were initiated promptly after the diagnosis. Following the third PE, no further exacerbation of TEN was observed. The patient was discharged on the 85th day. TEN is a rare and severe medication reaction with a poor prognosis, and its mortality rate in hemodialysis patients is over ten times higher than in the general population.
Because strict control of the serum phosphate (P) concentration using the intestinal Na/H exchanger 3 inhibitor (tenapanor) is expected, this retrospective study was performed involving 27 maintenance hemodialysis patients who switched from lanthanum carbonate to tenapanor and did not meet the exclusion criteria at the time. Twelve patients (44.4%) dropped out due to diarrhea, and 5 patients who eventually met the exclusion criteria were excluded, resulting in 10 patients for analysis. The dose of phosphate‒reducing drugs decreased from 4.6±1.9 tablets at the start to 2.4±0.9 tablets after 12 weeks (p<0.01). The level of serum P decreased from 5.4±0.9 mg/dL at the start to 4.2±0.5 mg/dL after 8 weeks (p<0.05), and to 3.9±0.9 mg/dL after 10 weeks (p<0.01). In addition, the final dose of tenapanor was 29.0±13.7 mg/day. Switching from lanthanum carbonate to tenapanor improved control of the serum P concentration and polypharmacy. However, it is important to promote tolerability through patient education because diarrhea occurred at a high rate, even at the starting dose.