Table 2. The characteristics of MPP with hyperkalemia and different levels of hypokalemia.
| Item | Normokalemia group | Mild hypokalemia group | Severe hypokalemia group | Hyperkalemia group | P |
|---|---|---|---|---|---|
| Case, n | 489 | 73 | 4 | 4 | |
| Gender | |||||
| Male, n | 238 | 73 | 4 | 3 | 0.000 |
| Female, n | 251 | 0 | 0 | 1 | |
| Age (months), median [IQR] | 25 [10–47] | 17 [7–35] | 9.5 [2.75–20] | 1 [1–10] | 0.007 |
| Season at enrollment, n (%) | 0.000 | ||||
| Spring (March–May) | 105 (21.5) | 41 (56.2)@ | 2 (50) | 0 | |
| Summer (June–August) | 70 (14.3) | 13 (17.8) | 0 | 0 | |
| Autumn (September–November) | 177 (36.2) | 1 (1.4)@ | 1 (25) | 2 (50) | |
| Winter (December–February) | 137 (28.0) | 18 (24.7) | 1 (25) | 2 (50) | |
| Heart rate (bpm), median [IQR] | 116 [109–122] | 117 [108–121] | 109 [98–117] | 109 [98–123] | 0.471 |
| Respiratory rate [bpm], median | 28 [25–32] | 28 [25–32] | 29 [24–33] | 28 [22–34] | 0.972 |
| Fever, n (%) | 339 | 54 | 3 | 2 | 0.694 |
| Max temperature (°C), median | 39.2 (38.7–39.5) | 39 (38.4–39.5) | 38.5 | 39.3 | |
| Fever duration [day], median | 4 [2–6] | 4 [3–5.5] | 8#% | 5.5 | |
| Wheezing, n (%) | 81 | 9 | 1 | 1 | 0.726 |
| Length of stay (day), median | 5 | 6 | 6 | 3.5 | 0.000 |
| WBC count (×109/L), median (IQR) | 9.32 (6.98–12.46) | 8.60 (6.82–11.34) | 8.97 (4.90–12.45) | 8.86 (6.01–17.96) | 0.818 |
| Ratio of neutrophils (%), median (IQR) | 57.10 (44.05–67.60) | 61.35 (44.95–70.33) | 57.75 (48.83–58.58) | 59.60 (29.25–73.98) | 0.996 |
| CRP (mg/L), median (IQR) | 9 (0–9.51) | 4.56 (0–11.49) | 2.71 (0–10.45) | 2.91 (0–6.80) | 0.700 |
| LDH (U/L), median | 261.5 (225.0–295.0) | 261 (228.5–289.0) | 241 | 311.5 (213.8–364.2) | 0.753 |
| Mild MP infection (serum anti-MP IgM titer =1:160), n (%) | 477 (86.3) | 72 (3) | 0 (0) | 4 (0.7) | |
| Severe MP infection (serum anti-MP IgM titer ≥1:320), n (%) | 12 (70.6) | 1 (1.4) | 4 (23.5) | 0 (0) |
@, mild hypokalemia group vs. normokalemia group, P<0.05; #, severe hypokalemia group vs. normokalemia group, P<0.05; %, severe hypokalemia group vs. mild hypokalemia group, P<0.05. MP, Mycoplasma pneumoniae pneumonia; IQR, interquartile range; WBC, whole blood cell; CRP, C-reactive protein; LDH, lactate dehydrogenase.