Kidney Week

Abstract: TH-PO205

Acute Mineral Metabolism Disorders Following Kidney Donation Are Not Different Compared to Those Observed in Other Surgical Procedures

Session Information

• Bone and Mineral Metabolism: Clinical - I
  October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Bone and Mineral Metabolism

• 402 Bone and Mineral Metabolism: Clinical

Authors

• Fonseca-Correa, Jorge Ignacio, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City, Mexico

Jorge Ignacio Fonseca-Correa,

• Tamez Pedroza, Luis, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City, Mexico

Luis Tamez Pedroza,

• Porto-Silva, Lucas, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City, Mexico

Lucas Porto-Silva,

• Alberú, Josefina, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City, Mexico

Josefina Alberú,

• Correa-Rotter, Ricardo, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City, Mexico

Ricardo Correa-Rotter,

• Ramirez-Sandoval, Juan Carlos, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City, Mexico

Juan Carlos Ramirez-Sandoval,

Background

Emerging studies have suggested that living kidney donors (LKD) have acute mineral metabolism (MM) abnormalities after unilateral nephrectomy related to loss of eGFR, in particular significant disturbances in P and Ca. Nevertheless, these changes have not been compared to controls undergoing other major surgical procedures. Our aim was to analyze acute MM abnormalities (serum Ca y P levels) in 3 groups: following laparoscopic (LN) vs. open nephrectomy (ON) and elective laparoscopic cholecystectomy (LC).

Methods

Single-center retrospective cohort study (n=293). Biochemical parameters were evaluated before and after surgery on days 1-6 and 30, in 100 consecutive LKD undergoing LN, compared with 91 subjects undergoing ON for kidney cancer or urolithiasis, and 102 subjects with gallstone disease undergoing elective LC. We excluded cases with CKD G4.

Results

LN group was younger compared to ON and LC groups (41±19, 58±14, and 58±19 years; p<0.001), and eGFR was higher in LN compared to ON and LC (101±17, 79±23, and 85±28 mL/min/1.73m²; p<0.001). As expected, only LN and ON reduced eGFR by day 2: -11.4 (-27 to 6) and -14 (-51 to 3) mL/min/1.73m² respectively. Serum P levels did not change significantly from baseline to day 1, but decreased by day 2 in all groups (LN=-1.2 [-1.6 to -0.2], ON=-1.0 [-1.7 to -0.1] and LC=-0.6 [-1.0 to 0.0] mg/dL) before normalizing by day 30 (Figure). Serum P decline was not modified by concurrent changes in eGFR in any group. Moderate hypophosphatemia (reduction to 1-2 mg/dL) was similarly present in all groups (LN 14%, ON 7%, and LC 12%; p=0.16). No hypophosphatemia <1 mg/dL occurred during follow-up. Transient non-corrected hypocalcemia and hypoalbuminemia appeared by day 3 in all groups.

Conclusion

Acute MM disturbances (serum P and Ca) occur after surgical procedures independent of changes in eGFR, and are not related to kidney donation or nephrectomy indicated for other causes. Postoperative slight hypophosphatemia is frequent and appears to be a multifactorial.