I ISMAIL1, A SAPONARA1, M MANTHA1,2, K BAVISHI1,2, S DHEDA1,2
1Department of renal medicine, Cairns Hospital,, Australia, 2School of Medicine and Dentistry, James Cook University, Cairns, , Australia
Aim: To analyse the epidemiology of Renal Impairment (RI) in newly diagnosed multiple myeloma patients in Far North Queensland (FNQ).
Background:Cairns hospital is a major referral centre in FNQ for haematological disease. Renal impairment (RI) is one of the most common complications in myeloma.
Methods: A single centre retrospective analysis of newly diagnosed multiple myeloma patients. Baseline investigations, treatment and mortality, were collected on newly diagnosed multiple myeloma patients over the last decade.
Results: There was a total of 93 newly diagnosed multiple myeloma patients over a 10-year. The mean age was 68 ±11 years, males 56%. The majority (82%) were Caucasians. The incidence of RI, defined as eGFR < 60 μmol/L/1.73m², was 48% at the time of diagnosis of myeloma.RI was strongly associated with a higher mean calcium (2.70 vs 2.37 mmols/L, 95% CI; 0.15 to 0.52 mmol/L, t₉₀ = 3.65, p <0.001), higher mean β-2-microglobulin levels (11.82 vs 3.03 mg/L, 95% CI; 3.49 to 14.08 mg/L, t₆₅=3.32, p =0.001) and higher mean free light chain levels (1535 vs 727 mg/L, 95% CI; -16 to 1633 mg/L, t₈₂=1.95, p=0.05). Patients who had RI were more likely to be readmitted (mean hospital admissions 30 vs 14, 95%CI -3 to 35, t₉₁=1.67, p = 0.09).There were 7 renal biopsies with cast nephropathy the commonest presentation. The mean eGFR improved by 7 mls/min/1.73m² (95%CI; -2.21 to -12.58) at six months (t₇₂=-2.84, p = 0.006).
Conclusions: Nearly half of newly diagnosed myeloma patients have renal impairment. Treatment for myeloma resulted in a nett improvement in eGFR after 6 months. However, they are more likely to be readmitted. Myeloma is uncommon in the indigenous population.
Dr A Saponara is a medical registrar at the Cairns Hospital.