Serum procalcitonin as a predictor of severity of pneumonia in under-five children: A prospective observational study

Table 1 Baseline characteristics of the included children, n (%)/mean ± SD

Characteristics	All patients (n = 200)	Bacterial (n = 39)	Viral (n = 15)	Atypical (n = 7)	P value
Age (months)	11.4 ± 8.8	28.4 ± 7.2	9.7 ± 5.6	35.2 ± 6.9	0.03
Age sub-groups
≤ 6 months	96 (48)	8 (20.5)	9 (60)	0 (0)	0.021
From 6 months to 1 year	43 (21.5)	14 (35.9)	4 (26.7)	0 (0)	0.58
> 1-5 year	61 (31.5)	17 (43.6)	2 (13.3)	7 (100)	0.042
Male	128 (64)	26 (66.7)	9 (60)	5 (71.4)	0.65
Duration of symptoms prior to admission (days)	2.5 ± 0.8	2.3 ± 0.7	3.1 ± 0.4	3.2 ± 0.1	0.92
Not immunized	31 (15.5)	7 (17.9)	3 (20)	2 (28.6)	0.34
Severe malnutrition	19 (9.5)	8 (20.5)	2 (13.3)	2 (28.6)	0.27
Clinical features
Fever	192 (96)	37 (94.8)	14 (93.3)	6 (85.7)	0.43
Cough	176 (88)	32 (82)	15 (100)	6 (85.7)	0.47
Rapid breathing	200 (100)	39 (100)	15 (100)	7 (100)	0.92
Chest retractions	200 (100)	39 (100)	15 (100)	7 (100)	-
Any danger sign1	159 (79.5)	34 (87.2)	13 (86.7)	5 (71.4)	-
Prior antibiotic use	109 (54.5)	24 (61.5)	8 (53.3)	4 (57.1)	0.69

¹Danger signs: (1) Lethargy or unconsciousness; (2) Convulsions; (3) Unable to feed or drink; (4) Stridor in a calm child; (5) Hypothermia; and (6) Cyanosis.

P < 0.05 has statistical significance.

Table 2 Investigations, clinical course and outcomes in included children, n (%)/mean ± SD

Characteristics	All patients (n = 200)	Bacterial (n = 39)	Viral (n = 15)	Atypical (n = 7)	P value
Complete blood count
Total leucocyte count (cumm)	15417.4 ± 5551.1	17417.2 ± 3254.8	14226.4 ± 2119.6	13112.4 ± 1792.2	0.39
Hemoglobin (g/dL)	10.6 ± 1.8	10.9 ± 1.4	11.0 ± 1.6	11.1 ± 1.2	0.76
Neutrophil (%)	84 ± 6.4	84 ± 6.1	72 ± 7.3	73 ± 7.1	0.59
Lymphocyte (%)	31 ± 5.2	28 ± 5.4	33 ± 6.1	32 ± 4.8	0.84
Platelet count (lakhs/cumm)	2.4 ± 0.9	2.4 ± 1.5	2.7 ± 1.2	2.6 ± 1.2	0.91
Liver function tests
Total bilirubin (mg/dL)	0.9 ± 0.2	1.1 ± 0.2	1.4 ± 0.3	0.8 ± 0.1	0.65
Total protein (g/L)	7.7 ± 0.9	7.7 ± 0.8	7.6 ± 1.1	7.6 ± 0.9	0.77
Aspartate transaminase (U/L)	41 ± 8.4	36 ± 7.9	45 ± 8.1	44 ± 7.7	0.44
Alanine transaminase (U/L)	37 ± 6.5	36 ± 6.7	39 ± 6.1	38 ± 6.6	0.82
Renal function tests
Urea (mg/dL)	29 ± 8.4	29 ± 8.1	27 ± 9.1	28 ± 8.8	0.69
Creatinine (mg/dL)	0.8 ± 0.2	0.8 ± 0.2	0.8 ± 0.2	0.8 ± 0.2	0.93
Inflammatory markers
Erythrocyte sedimentation rate (mm/hour)	28 ± 12	23 ± 11	32 ± 8	26 ± 10	0.46
C-reactive protein (mg/L)	22 ± 9	42 ± 6	28 ± 7	20 ± 5	0.37
Chest X ray findings
Heterogenous opacities/infiltrates	106 (53)	14 (35.9)	13 (86.7)	6 (85.7)	0.07
Consolidation	73 (36.5)	25 (64.1)	2 (13.3)	1 (14.3)	P < 0.01
Duration of antibiotics use
5-10 days	142 (71)	26 (66.7)	15 (100)	7 (100)	-
> 10 days	58 (29)	13 (33.3)	0 (0)	0 (0)	0.002
Type of respiratory support
Nasal cannula/face mask	200 (100)	39 (100)	15 (100)	7 (100)	-
Continuous positive airway pressure	43 (21.5)	7 (17.9)	3 (13.3)	1 (14.3)	0.63
Heated humidified high flow nasal cannula	40 (20)	15 (38.5)	6 (40)	3 (42.9)	0.38
Mechanical ventilation	36 (18)	6 (15.4)	4 (26.6)	1 (14.3)	0.71
Pneumonia severity types
Moderate	115 (57.5)	19 (48.7)	9 (60)	5 (71.4)	0.33
Severe	49 (24.5)	13 (33.3)	4 (26.7)	1 (14.3)	0.27
Very severe	36 (18)	7 (18)	2 (13.3)	1 (14.3)	0.48
Outcomes
Discharged	182 (91)	33 (84.6)	13 (86.7)	7 (100)	0.51
Died	18 (9)	6 (15.4)	2 (13.3)	0	0.42

P < 0.05 has statistical significance.

Table 3 Comparison of serum procalcitonin level as per the disease severity distribution, mean ± SD

Severity distribution as per the etiology	Serum procalcitonin levels (ng/mL)		P value
	Day 1	Day 5
Moderate	0.47 ± 0.42	0.26 ± 0.18	0.09
Bacterial	2.14 ± 0.77	1.92 ± 0.85	0.06
Viral	0.32 ± 0.17	0.41 ± 0.19	0.29
Atypical	0.31 ± 0.14	0.37 ± 0.15	0.47
Severe	2.04 ± 1.5	3.14 ± 4.1	< 0.01
Bacterial	7.38 ± 1.01	9.56 ± 3.92	< 0.01
Viral	0.45 ± 0.16	0.49 ± 0.17	0.27
Atypical	0.38 ± 0.15	0.41 ± 0.17	0.41
Very severe	4.21 ± 2.37	7.46 ± 3.62	< 0.01
Bacterial	14.86 ± 2.19	19.27 ± 3.54	< 0.01
Viral	0.54 ± 0.22	0.72 ± 0.18	0.25
Atypical	0.41 ± 0.19	0.55 ± 0.16	0.34

P < 0.05 has statistical significance.