Background: Paraproteins often cause factitious biochemical measurements by forming opaque precipitates with the test reagents and interfering with various automated assays. These interferences may be difficult to anticipate as they are intermittent and patient-specific. Increased IgM has been shown to result in the underestimation of uric acid levels and pseudo-hypouricemia; however, there are no reported cases of pseudo-hyperuricemia in the setting of paraproteinemia. Case presentation: We present a case of Waldenström’s Macroglobulinemia (WM), resulting in a marked elevation of the uric acid level in the absence of tumor lysis syndrome (TLS). On evaluation, it was noted that the elevation in the uric acid levels was spurious, potentially due to high IgM levels resulting in increased serum viscosity. Identifying actual and pseudo-abnormal laboratory results is critical to guide further workup and conserve scarce healthcare resources. The absence of other concomitant laboratory abnormalities and clinical symptoms should raise a suspicion of factitious results. In addition to uric acid, many other assays are affected by paraproteinemia, commonly including electrolytes, lipids, glucose, and liver function tests.

Objective Chronic kidney disease is a worldwide public health issue, with increasing prevalence resulting in high morbidity and mortality. As a result, recognizing and treating it early can lead to improved outcomes. We hypothesized that some providers might be more comfortable making this diagnosis than others. Methods Retrospective study of 380 patients with chronic kidney disease seen between 2012 and 2016 in an outpatient setting. Results Three hundred and sixteen patients were treated by physicians and sixty-four by advanced practice providers. Chronic kidney disease was identified by the primary care providers in 318 patients (83.6%). Patients recognized with chronic kidney disease were older, 76 ± 8.8 vs 72 ± 7.45 years, p = 0.001; had lower GFR, 37 [29, 46] vs 57 [37, 76] ml/min/1.73 m 2 , p < 0.0001 and were more likely to be seen by a physician compared to an advanced practice provider: 272/316 (86%) vs 46/64 (71.8%), p = 0.008. In multivariate analyses, care by a physician, OR = 2.27 (1.13–4.58), p = 0.02 was associated with increased recognition of chronic kidney disease. On the other hand, higher GFR was associated with decreased diagnosis of chronic kidney disease, OR = 0.95 (0.93–0.96), p < 0.0001. Conclusion The odds of chronic kidney disease recognition were higher amongst physicians in comparison to non-physician providers.