Table 3.

Characteristics of patients admitted to hospital after the first and second presentation

Characteristics	Admitted after first presentation (n = 1068)	Admitted after second presentation (n = 34)	P-value
Sex (male), %	62	62	0.97
Age (years), mean ± SD	64 ± 14	71 ± 14	0.005
BMI (kg/m2), mean ± SD	27 ± 5	27 ± 5	0.83
Race, %			0.49
Asian	3	6
Black or African descent	5	9
White or Caucasian	86	82
Other or unknown	6	3
Tobacco use, %			0.03
Current	7	0
Prior	22	41
Never	47	44
Unknown	24	15
CFS (AU), mean ± SD	3.7 ± 1.8	4.0 ± 1.7	0.34
Patient identification, n			0.37
Symptoms only	75	88
Symptoms and contact	15	12
No symptoms but contact	5	0
Routine screening	5	0
COVID-19 test result, n			0.77
Positive	92	91
Negative	5	6
Intermediate/unknown	2	3
Abnormality on X-ray (yes), n	44	15	0.002
Abnormality on CT scan (yes), n	41	6	<0.001
Comorbidities, %
Obesity	23	16	0.33
Hypertension	83	82	0.92
Diabetes mellitus	40	47	0.41
Coronary artery disease	30	35	0.49
Heart failure	21	18	0.65
Chronic lung disease	12	18	0.37
Active malignancy	7	9	0.69
Autoimmune disease	5	9	0.31
Primary kidney disease, %
Primary glomerulonephritis	16	15	0.84
Pyelonephritis	3	0	0.34
Interstitial nephritis	5	3	0.66
Hereditary kidney disease	10	9	0.92
Congenital diseases	2	0	0.43
Vascular diseases	12	18	0.32
Secondary glomerular disease	7	9	0.59
Diabetic kidney disease	22	33	0.12
Other	13	6	0.25
Unknown	11	6	0.37
Dialysis (yes), %	67	79	0.13
HDa	99	100	0.73
PDa	1	0
Residual diuresis ≥200 mL/daya	33	48	0.08
Transplant waiting list statusa, %			0.39
Active on waiting list	11	7
In preparation	10	7
Temporarily not on list	10	4
Not transplantable	64	81
Unknown	5	0
Kidney transplant (yes), %	34	21
Time since transplantationb, %			0.57
<1 year	8	14
1–5 years	31	43
>5 years	61	43
Medication, %
ACE inhibitor use (yes)	17	21	0.37
ARB inhibitor use (yes)	15	24	0.18
Immunosuppressant use, %
Prednisone	86	91	0.63
Tacrolimus	67	64	0.79
Cyclosporine	11	0	0.49
Mycophenolate	58	45	0.39
Azathioprine	4	0	0.75
mTOR inhibitor	12	18	0.81
Disease characteristics
Days from symptom onset, median (IQR)	2 (0–5)	1 (0–4)	0.32
Presenting symptoms, %
Sore throat	13	18	0.63
Cough	58	56	0.93
Shortness of breath	44	24	0.05
Fever	68	50	0.02
Headache	13	15	0.67
Nausea or vomiting	13	6	0.21
Diarrhoea	18	15	0.37
Myalgia or arthralgia	23	27	0.28
Vital signs, mean ± SD
Temperature (°C)	37.6 ± 1.1	37.4 ± 1.2	0.21
Respiration rate (per min)	20 ± 6	17 ± 4	0.006
O2 saturation room air (%)	93 ± 6	96 ± 3	0.003
SBP (mm Hg)	135 ± 25	129 ± 22	0.19
DBP (mm Hg)	76 ± 15	69 ± 15	0.009
Pulse rate (bpm)	85 ± 16	74 ± 11	<0.001
Laboratory test results
Creatinine increase (>25%)b	33	25	0.52
Lymphocytes (×1000/µL), median (IQR)	0.9 (0.5–1.3)	0.7 (0.5–1.1)	0.42
CRP (mg/L), median (IQR)	38 (10–95)	29 (5–63)	0.14

Groups were compared using Student’s t, Wilcoxon or chi-square test as appropriate. Obesity is defined as BMI >30 kg/m². DBP, diastolic blood pressure; O₂, oxygen; SBP, systolic blood pressure; mTOR, mechanistic target of rapamycin.

^aIn dialysis patients only.

^bIn transplant recipients only.