Table 5.

Indications for antibiotic treatment for study populations of the combined IV model

Indication for antibiotic therapy	Co-amoxiclav and amoxicillin (n = 174)	Benzylpenicillin (n = 64)	Flucloxacillin (n = 72)	Piperacillin (n = 70)
Suspected or proven sepsis (including bacteraemia), n (%)	81 (46.6)	49 (76.6)	34 (47.2)	18 (21.7)
Surgical prophylaxis, n (%)	38 (21.8)	0 (0)	11 (15.3)	4 (4.8)
LRTI (including CAP), n (%)	18 (10.3)	0 (0)	5 (6.9)	20 (24.1)
Intra-abdominal infection (including NEC), n (%)	12 (6.9)	0 (0)	0 (0)	4 (4.8)
Medical prophylaxis, n (%)	9 (5.2)	12 (18.8)	1 (1.4)	7 (8.4)
Meningitis, n (%)	7 (4)	1 (1.6)	1 (1.4)	0 (0)
Urinary tract infection, n (%)	3 (1.7)	0 (0)	0 (0)	0 (0)
Hospital-acquired pneumonia (HAP), n (%)	2 (1.1)	2 (3.1)	0 (0)	4 (4.8)
Ventilator-associated HAP, n (%)	0 (0)	1 (1.6)	0 (0)	4 (4.8)
Aspiration pneumonia, n (%)	0 (0)	0 (0)	0 (0)	2 (2.4)
Pharyngitis, n (%)	1 (0.6)	1 (1.6)	0 (0)	1 (1.2)
Skin or soft tissue infection, n (%)	1 (0.6)	3 (4.7)	19 (26.4)	0 (0)
Septic arthritis or osteomyelitis, n (%)	1 (0.6)	2 (3.1)	4 (5.6)	0 (0)
Febrile neutropenia or neutropenic sepsis, n (%)	1 (0.6)	0 (0)	1 (1.4)	6 (7.2)
Endocarditis, n (%)	0 (0)	1 (1.6)	2 (2.8)	0 (0)
Congenital pneumonia, n (%)	0 (0)	2 (3.1)	0 (0)	0 (0)
Other, n (%)	15 (8.6)	2 (3.1)	2 (2.8)	13 (15.7)

LRTI, lower respiratory tract infection; CAP, community-acquired pneumonia, NEC, necrotizing enterocolitis. Note some patients had more than one indication for antibiotic therapy recorded, hence the total number of indications is greater than the total number of subjects. Note the total number of patients across all penicillin groups is higher than the overall total n = 370 because 10 participants contributed samples for two different penicillins.