Table 4 Historical, clinical and laboratory data of the subgroups considering as risk factors prior antibiotic treatment, age less than 2 years and fever higher than 38.5 °C

Mean Age (years)

–

–

–

5.5 ± 3.7

3.8 ± 3.1

< 0.005

4.1 ± 3.1

6.9 ± 4.1

< 0.0001

Median Age (years)

–

–

–

4.8

(0.4–13.2)

2.7

(0.3–13.5)

< 0.005

3.3

(0.4–12-6)

6.3

(0.3–13-5)

< 0.0001

Hospitalization (days)

9 ± 3.4

8.5 ± 7.8

NS

8.7 ± 5.2

8.5 ± .8.7

NS

8.8 ± 7.1

8.1 ± 5.8

NS

Prior antibiotic treatment (days)

1.5 ± 3.1

2.7 ± 2.9

< 0.05

–

–

2.3 ± 3.1

2.6 ± .2.9

NS

Symptom duration (days)

4.2 ± 3.9

5.3 ± 4.2

NS

6 ± 4.4

3.7 ± 3.2

< 0.0001

5.2 ± 4.3

4.4 ± 3.4

NS

WBC (10^3/mmc)

18,440 ± 6115

14,370 ± 4550

< 0.0001

14,550±

5090

16,920±

5450

< 0.01

16,250 ± 5405

13,470 ± 4680

< 0.01

CPR (mg/dl)

9.5 ± 7.7

6.8 ± 11

NS

6.1 ± 5.9

9.6 ± 14.1

NS

9.2 ± 11.3

2.8 ± 3.4

< 0.0001

Antibiotic treatment (days)

8.9 ± 3.4

8.2 ± 4.5

NS

9.2 ± 4.7

7.3 ± 3.2

< 0.005

8.6 ± 3.6

8 ± 5.2

NS

Antibiotic treatment (mg/kg/die)

75 ± 17

66 ± 20

< 0.01

69 ± 20

69 ± 19

NS

72 ± 19

59 ± 19

< 0.001

Complications (%, n° pts)

14 (6)

8 (8)

NS

65 (9)

35 (5)

NS

10 (11)

8 (3)

NS

Fever (%, n° pts)

86 (36)

69 (73)

< 0.05

74 (64)

82 (50)

NS

–

–

–

Othalgia (%, n° pts)

48 (20)

88 (93)

< 0.0001

78 (67)

75 (46)

NS

73 (83)

91 (30)

< 0.05

Othorrea (%, n° pts)

26 (11)

25 (26)

NS

30 (26)

18 (11)

NS

26 (28)

24 (9)

NS

Protrusion of auricle (%, n° pts)

76 (32)

60 (63)

NS

62 (53)

69 (42)

NS

67 (76)

59 (19)

NS

Retroauricular swelling (%, n° pts)

78 (33)

54 (56)

< 0.01

54 (63)

57 (35)

NS

65 (74)

47 (15)

NS

Retroauricular erythema (%, n° pts)

74 (31)

72 (75)

NS

70 (60)

75 (46)

NS

73 (83)

72 (23)

NS

Retroauricular pain (%, n° pts)

28 (12)

60 (62)

< 0.001

46 (54)

28 (46)

NS

46 (52)

69 (22)

< 0.05