Table 4.

Laboratory characteristics of patients on hemodialysis with and without an undetected severe acute respiratory syndrome coronavirus 2 infection identified in the subsequent ≥3 d

VariableUnaffected Patients, Mean±SD, NCoronavirus Disease 2019+, Patients, Mean±SD, N
Number of patients on HD29,32411,166
Albumin (g/dl)a3.79±0.40; 13,7233.69±0.46; 5252
Change in albumin (g/dl)b−0.002±0.25; 13,139−0.03±0.27; 5012
Creatinine (mg/dl)a8.42±3.06; 13,3238.41±3.14; 5113
Change in creatinine (mg/dl)b0.08±1.40; 12,7110.16±1.52; 4860
Bicarbonate (mmol/L)a24.24±3.05; 13,39524.22±3.22; 5137
Change in bicarbonate (mmol/L)b0.02±2.97; 12,772−0.16±3.12; 4864
BUN (mg/dl)a56.21±18.53; 14,94156.17±19.27; 5631
Change in BUN (mg/dl)b−0.21±15.50; 14,400−0.13±16.55; 5416
URRa74.92±6.52; 14,27375.05±6.61; 5348
Change in URRb0.09±5.89; 13,5480.07±6.08; 5054
Sodium (mmol/L)a137.50±3.37; 13,139137.08±3.52; 5046
Change in sodium (mmol/L)b−0.10±2.83; 29,324−0.25±3.10; 4772
Potassium (mmol/L)a4.80±0.68; 16,0514.78±0.70; 6217
Change in potassium (mmol/L)b0.01±0.60; 15,499−0.01±0.63; 6003
Phosphate (mg/dl)a5.55±1.74; 15,4895.37±1.71; 5913
Change in phosphate (mg/dl)b0.01±1.48; 14,918−0.03±1.46; 5692
Chloride (meq/L)a98.66±4.14; 12,60298.33±4.13, 4702
Change in chloride (meq/L)b−0.19±3.35; 11,708−0.24±3.50; 4450
Calcium (mg/dl)a8.89±0.69; 15,4208.78±0.73; 5878
Change in calcium (mg/dl)b0.02±0.58; 14,882−0.07±0.60; 5659
Corrected calcium (mg/dl)a9.06±0.66; 12,8659.04±0.71; 4903
Change in corrected calcium (mg/dl)b0.01±0.54; 12,148−0.03±0.59; 4608
iPTH (pg/ml)a489.46±454.13; 10,090497.22±490.12; 3801
Change in iPTH (pg/ml)b−21.39±280.41; 7245−21.84±296.17; 2734
Ferritin (ng/ml)a1029.94±576.07; 82291197.32±900.22; 3138
Change in ferritin (ng/ml)b52.90±505.99; 4400142.00±739.89; 1589
TSAT (%)a33.07±14.10; 13,05131.29±14.42; 5008
Change in TSAT (%)b0.17±15.33; 12,310−1.59±16.54; 4689
Hgb (g/dl)a10.76±1.24; 29,32410.61±1.26; 11,166
Change in Hgb (g/dl)b0.05±1.07; 29,3240.01±1.13; 11,166
Platelet count (×109/L)a195.49±72.47; 11,378192.35±77.10; 4293
Change in platelet count (×109/L)b−1.93±49.23; 10,595−7.82±55.06; 3963
WBC count (×109/L)a6.93±2.36; 13,0436.55±2.39; 5027
Change in WBC count (×109/L)b0.03±1.76; 12,344−0.36±1.93; 4733
% of neutrophilsa66.11±9.50; 17,21566.59±9.53; 6941
Change in % of neutrophilsb0.06±6.72; 14,9310.47±7.37; 5997
% of lymphocytesa20.22±7.98; 17,21519.76±7.96; 6941
Change in % of lymphocytesb−0.04±4.99; 14,931−0.53±5.57; 5997
% of monocytesa6.38±1.90; 17,2156.69±2.14; 6941
Change in % of monocytesb0.02±1.48; 14,9310.37±1.82; 5997
% of eosinophilsa4.29±2.88; 17,2123.95±2.84; 6939
Change in % of eosinophilsb−0.10±2.03; 14,927−0.40±2.28; 5995
% of basophilsa0.75±0.47; 17,2060.73±0.45; 6934
Change in % of basophilsb0.05±0.54; 14,9170.03±0.52; 5988
  • All variables were included in the ML prediction model to classify the risk of an individual HD patient having a SARS-CoV-2 infection being identified in the following ≥3 d. HD, hemodialysis; Hgb, hemoglobin; WBC, white blood cell; TSAT, transferrin saturation; URR, urea reduction ratio; iPTH, intact parathyroid hormone; ML, machine learning; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.

  • a Mean values of laboratory variables 1–14 d before the prediction date (i.e., 3 d before suspicion of SARS-CoV-2 infection in standard clinical practice).

  • b Mean values of the difference in laboratory variables 31–60 d to 1–14 d before the prediction date.