MO756MANAGEMENT OF CHRONIC HIPERKALAEMIA IN CLINICAL PRACTICE IN HAEMODIALYSIS

Background and Aims

Patients with chronic kidney disease (CKD) on haemodialysis (HD) have an increased risk of hyperkalaemia, a serious and potentially fatal electrolyte disorder. New effective strategies for managing hyperkalaemia have recently become available. However, as yet, there is insufficient experience in routine clinical practice in HD.

The aim of our study was to report the prevalence of chronic hyperkalaemia and analyse the effects of different treatment strategies on potassium management, ratio of adherence and gastrointestinal symptoms in our HD population.

Method

A 12-week, prospective, single-centre study in HD patients with chronic hyperkalaemia (>5.5 mmol/l). Three study phases were established: Phase 1 — dietary advice (DA); Phase 2 — calcium polystyrene sulfonate resins (CPSRs); and Phase 3 — patiromer. In each phase, we analysed sociodemographic data, related biochemical data, treatment adherence and compliance (Simplified Medication Adherence Questionnaire [SMAQ]), gastrointestinal symptoms (Gastrointestinal Symptom Rating Scale [GSRS]), HD characteristics and usual medical treatment.

Results

29.2% hyperkalaemia (46% mild); 13 patients (61.5% female); mean age 63.8 ± 14.1 years and 46.4 ± 41.6 months on HD. Serum K values decreased significantly (*p <0.05) only in phase 3 (–0.75 mmol/l), with a higher percentage of patients reaching optimal K range. Compared with CPSRs, patiromer yielded significantly better overall GSRS scores: abdominal pain (3.7 versus 2.5), constipation (7.1 versus 5.3), indigestion (6.2 versus 5.6); and also better treatment compliance. No significant changes were found in any other biocbhemical data, HD characteristics or usual medication over the course of the study.

Conclusion

Chronic hyperkalaemia is a highly prevalent disorder on our HD unit. Compared to dietary advice and traditional potassium binders; patiromer was effective in managing chronic hyperkalaemia, leading to improvement in gastrointestinal symptoms and treatment adherence with no associated severe adverse effects. Thus, considering our results, we shall consider patiromer a first-line treatment for chronic hyperkalaemia in our patients with HD.

Acute interstitial nephritis associated with immune checkpoint inhibitors: a single-centre experience

BACKGROUND

Checkpoint inhibitors (CPIs) are used to treat solid organ metastatic malignancies. They act by triggering a vigorous immune response against tumoural cells, preventing their proliferation and metastasis. However, this is not a selective response and can cause immune-related adverse events (irAEs). The kidney can potentially be damaged, with an incidence of irAEs of 1-4%. The most frequent type of toxicity described is acute interstitial nephritis (AIN).

METHODS

We conducted a study of patients with solid organ metastatic malignancies treated with immunotherapy who developed acute renal injury and underwent kidney biopsy in the last 14 months at the Vall d'Hebron University Hospital.

RESULTS

In all, 826 solid organ malignancies were treated with immunotherapy in our centre, 125 of them (15.1%) developed acute kidney injury (AKI), 23 (18.4% of AKI) visited the nephrology department and 8 underwent kidney biopsy. The most frequent malignancy was lung cancer, in five patients (62%), followed by two patients (25%) with melanoma and one patient (12%) with pancreatic cancer. Four patients (50%) had already received previous oncological therapy, and for the remaining four patients (50%), CPI was the first-line therapy. Five patients (62%) were treated with anti-programmed cell death protein 1, three patients (37%) received anti-programmed death ligand 1 and two (25%) patients were treated in combination with anti-cytotoxic T-lymphocyte antigen 4. The time between the start of CPI and the onset of the AKI ranged from 2 to 11 months. The most frequent urine findings were subnephrotic-range proteinuria, with a mean protein:creatinine ratio of 544 mg/g (standard deviation 147) and eosinophiluria. All patients were biopsied after being diagnosed with AIN. Three patients (37%) received treatment with pulses of methylprednisolone 250-500 mg/day and five patients (62%) received prednisone 1 mg/kg/day. Seven patients (87%) experienced recovery of kidney function and one patient (12%) progressed to chronic kidney disease.

CONCLUSIONS

We report on eight patients with CPI-related AIN diagnosed in the last 14 months at our centre. The novel immunotherapy treatment of metastatic solid organ malignancies carries a higher risk of irAEs. The kidney is one of the most commonly affected organs, frequently presenting as an AIN and exhibiting a favourable response to steroid treatment.

P0306ACUTE KIDNEY INJURY AFTER CHECKPOINT INHIBITOR TREATMENT: FACING THE FUTURE

Background and Aims

Checkpoint inhibitors (CPI) are used to treat solid organ metastatic malignancies. They act on by triggering a vigorous immune response against tumoral cells, preventing their proliferation. CPIs reinvigorate antitumor immune responses by interrupting co-inhibitory signaling pathways and promote immune-mediated elimination of tumor cells.This is not a selective response, deriving in immune related adverse events (irAEs). The kidney can potentially be damaged with an incidence of 13-29%. The most frequent type of toxicity is acute interstitial nephritis (AIN).

Method

We evaluated all the patients with solid organ metastatic malignancies treated with immunotherapy that developed acute renal injury (AKI) and underwent to kidney biopsy from March 2018 to November 2019 at Vall d’Hebron University Hospital.

Results

11 patients with solid organ metastatic malignancies treated with immunotherapy developed AKI and underwent to kidney biopsy during the study period. The most frequent malignancy was lung cancer - in 6 patients-, followed by 3 patients with melanoma. 8 patients (72%) had already received previous oncological therapy, and for the remaining 3 patients (27%), CPI was the first line therapy. 8 patients (72%) were treated with anti-PD1 (programmed cell death protein 1), 4 patients (36 %) received anti PDL-1 (programmed death-ligand 1) 1 of these patients in combination with an anti CTLA-4 (cytotoxic T-lymphocyte antigen 4) and another patient received both anti PD1 and anti PDL-1. The time between the start of CPI and the onset of the AKI ranged between 2-11 months. The most frequent urine findings were subnephrotic range proteinuria with a mean protein/creatinine (mg/g creatinine) 503.6 ± 190.5 and leukocyturia in 9 of 11 patients. Mean creatinine (mg/dl) at diagnosis was 3.4 ± 1.3. 10 out of the 11 patients were diagnosed of AIN after performing a kidney biopsy. The remaining patient presented chronic changes (IFTA and glomerulosclerosis) in the biopsy, performed after receiving steroids for a month. 3 patients who presented AIN received pulses of methylprednisolone 250-500mg as induction treatment and 7 patients received prednisone 1mg/kg/day. Mean prednisone accumulated dose (mg) during the first month of treatment was 1387.5 ± 540. 9 patients experienced complete recovery of kidney function and two patients progressed to CKD.

Conclusion

We reported 11 patients who presented AKI associated to CPI treatment and underwent to kidney biopsy in the last 20 months at our center. 10 out of 11 presented biopsy confirmed CPI related AIN. In our experience, CPI related AIN is the most frequent renal lesion associated to the novel immunotherapy treatments. This entity seems to have good renal prognosis as long as steroid treatment is early started.