Pyogenic liver abscess: An audit of 10 years’ experience

Table 1 Summary of laboratory results at initial presentation

	Reference range	No. of patients measured	mean ± SD	% of patients outside reference range
White cell count (× 109/L)	4.0-11.0	62	15.0 ± 6.3	74%
Neutrophil count (× 109/L)	2.0-8.0	62	12.9 ± 5..9	82%
Haemoglobin (g/L)	135-180	62	118 ± 21	24% Hb < 100 g/L
Platelets (× 109/L)	150-400		320 ± 202	42%
C-reactive protein (mg/L)	< 5	47	272 ± 119	100% (47/47)
Urea (mmol/L)	3.1-8.1	62	8.2 ± 5.96	29% Urea > 8.1 mmol/L
Creatinine (μmol/L)	60-100	62	105 ± 60	42% Cr > 100 μmol/L
				16% Cr > 150 μmol/L
Albumin (g/L)	35-46	62	30 ± 7.0	73%
AST (U/L)	12-36	61	127 ± 301	67%
ALT (U/L)	5-40	62	118 ± 222	73%
ALP (U/L)	41-119	61	209 ± 140	71%
GGT (U/L)	5-65	62	191 ± 201	75%
Bilirubin (μmol/L)	3-18	61	30 ± 39	54% Bil > 18 μmol/L 13% Bil > 50 μmol/L
Glucose (mmol/L)	3.5-5.5	47	7.8 ± 2.6	15% (7/47) Glucose > 10 mmol/L
INR	≤ 1.5	53	1.3 ± 0.56	13% (7/53)

AST: Aspartate transaminase; ALT: Alanine transaminase; ALP: Alkaline phosphatase; Bil: Serum bilirubin; GGT: γ glutamyl transpeptidase; INR: International normalized ratio; RR: Reference range. Reference ranges supplied by local pathology laboratory.

Table 2 Summary of physical examination findings on presentation

Clinical finding	n (%)
Fever (T > 37.5)	33 (59)
Hypotension (SBP < 100)	7 (13)
Tachycardia (HR ≥ 100)	29 (52)
Peritonism
None	49 (86)
Localized guarding	8 (14)
Generalized peritonism	0 (0)
Location of tenderness
Non tender abdomen	20 (35)
Right upper quadrant	22 (39)
Other abdominal tenderness	15 (26)

HR: Heart rate in beats per minute; SBP: Systolic blood pressure in mmHg; T: Body temperature in degrees Celsiu.

Table 3 Summary of microbiology results for blood culture results, liver abscess aspirate culture results, and presumed causative pathogen

Organism	n (% of patients with culture results)
	Positive blood cultures	Positive liver aspirate cultures	Causative pathogen
Streptococcus milleri	8 (14)	12 (24)	16 (25)
Klebsiella species	9 (16)	8 (16)	13 (21)
K. pneumoniae	7	8	11
K. oxytoca	1	0	1
K. terrigena	1	0	1
Escherichia coli	6 (11)	3 (5.9)	10 (16)
Mixed1	2 (3.6)	6 (12)	5 (8)
Fusobacterium necrophorum	1 (1.8)	1 (2.0)	2 (3.2)
Pseudomonas aeruginosa	0 (0)	1 (2.0)	1 (1.6)
Lactobacillus	0 (0)	1 (2.0)	1 (1.6)
Corynebacterium urealyticum	0 (0)	1 (2.0)	1 (1.6)
Citrobacter koseri	0 (0)	1 (2.0)	1 (1.6)
Staphylococcus aureus2	1 (1.8)	0 (0)	0 (0)
Causative organism not identified	-	-	13 (21)
Total negative	29 (52)	17 (33)	-
Total positive	27 (48)	34 (67)	50 (79)
Total number of patients with available culture results	/55	/51	/63

¹Includes 2 cases of Clostridium perfringens;

²Discordant with liver abscess microbiology. Likely contaminant.

Table 4 Summary of the presumed aetiology of the patients’ pyogenic liver abscesses

Aetiology	n (%)
Cryptogenic	20 (34)
Biliary	14 (22)
Portal (e.g. appendicitis, diverticulitis)	12 (20)
Haematogenous (other bacteremic source)	7 (11)
Direct (e.g. pericholecystic abscess, RFA)	6 (9.4)

RFA: Radiofrequency ablation.

Table 5 Summary of interventions

Initial intervention (%)		→	Secondary intervention (%)		→	Further interventions (%)
AB	5 (7.9)	→	RA	1/5 (20)
			Other	1/5 (20)
RD	43 (68)	→	RA	1/43 (2.3)
			SG	5/43 (12)
			RD	13/43 (30)	→	SG	1/13 (7.7)
						RD	3/13 (23)
RA	11 (18)	→	RD	2/11 (18)
			SG	2/11 (18)
SG	2 (3.2)		-			-
Other	2 (3.2)	→	SG	1/2 (50)

AB: Antibiotics only; RA: Image guided aspiration of abscess; RD: Image guided insertion of indwelling drain; SG: Surgical intervention. Note that all patients received intravenous antibiotics before any interventional treatment.

Table 6 Complications occurring in 21 patients

Complication	n
Acute renal failure	7
Abdominal collection/sepsis	4
Thoracic empyema/large pleural effusion requiring surgical drainage	4
Multiple organ failure	2
Biliary fistula	2
Hemorrhage from percutaneous drainage	2
Portal vein thrombosis	1
Hepatic vein thrombosis	1
Subcapsular hematoma from percutaneous drainage	1
Myocardial infarction	1
Necrosis of terminal phalanges	1

Table 7 Univariate analysis of factors that may lead to failure in initial percutaneous therapy

	Treatment successful	Treatment failure	P-value
Demographic characteristics and history
Age (yr), mean (95% CI)	67 (62-73)	63 (57-69)	0.26
Sex (M:F)	20:11	15:08	1.00
Prodrome (days), median (IQR)	7 (3-20)	7 (5-14)	0.88
History of gallstone disease, n (%)	8 (27)	5 (22)	0.76
History of diabetes mellitus, n (%)	4 (13)	3 (13)	1.00
Chronic renal failure, n (%)	1 (3.3)	1 (4.4)	1.00
Current cancer, n (%)	6 (20)	5 (22)	1.00
Examination findings, n (%)
Fever	16 (53)	12 (63)	0.56
Tachycardia	13 (43)	11 (58)	0.39
Hypotension	4 (13)	1 (5.3)	0.64
Laboratory findings, mean (95% CI)
Leucocytes (× 109/L)	15.2 (13.1-17.4)	13.6 (11.2-16.0)	0.30
Neutrophil (× 109/L)	12.8 (10.8-14.9)	11.7 (9.5-13.8)	0.43
Haemoglobin (g/L)	114 (106-121)	120 (110-130)	0.26
Platelet (× 109/L)	341 (255-426)	319 (250-388)	0.70
Urea (mmol/L)	9.3 (6.8-11.9)	6.5 (5.3-7.7)	0.07
Creatinine (μmol/L)	110 (83-138)	103 (86-121)	0.70
CRP (mg/L)	287 (236-338)	258 (193-324)	0.47
Albumin (g/L)	32 (29-35)	28 (25-31)	0.045
AST (U/L)	187 (30-344)	70 (43-97)	0.19
ALT (U/L)	149 (37-260)	84 (55-114)	0.33
GGT (U/L)	193 (115-271)	183 (96-269)	0.85
ALP (U/L)	201 (154-249)	203 (143-262)	0.97
Bilirubin (μmol/L)	29 (13-45)	26 (19-32)	0.75
Glucose (mmol/L)	7.9 (6.7-9.0)	7.6 (6.4-8.9)	0.79
INR	1.2 (1.1-1.3)	1.4 (1.0-1.8)	0.24
Microbiology
Positive blood culture, n (%)	12 (43)	9 (47)	0.78
Positive aspirate culture, n (%)	17 (61)	17 (85)	0.11
Organism, n (%)			0.19
Streptococcus milleri	8 (26)	8 (35)
Klebsiella species	5 (16)	7 (30)
Escherichia coli	6 (19)	0 (0)
Other	6 (19)	4 (17)
Negative cultures	6 (19)	4 (17)
Imaging findings
Multiple abscesses, n (%)	7 (24)	10 (45)	0.14
Side of liver, n (%)			0.10
Left	5 (17)	2 (10)
Right	23 (77)	13 (62)
Bilateral involvement	2 (7)	6 (29)
Abscess diameter, median (IQR)	6.0 (3.8-9.5)	6.5 (5.0-8.4)	0.83
Diameter > 5 cm	11 (41)	7 (35)	1.00
Presence of gas, n (%)	5 (17)	1 (5)	0.38
Biliary duct dilatation, n (%)	6 (20)	2 (10)	0.45
Intervention
Percutaneous drain insertion (vs percutaneous aspiration)	24 (77)	19 (83)	0.74
Cause
Presumptive cause, n (%)			0.60
Cryptogenic	8 (29)	9 (41)
Biliary	7 (25)	5 (23)
Portal	6 (21)	4 (18)
Haematogenous	5 (18)	3 (14)
Direct	2 (7)	1 (5)

AST: Aspartate transaminase; ALT: Alanine transaminase; ALP: Alkaline phosphatase; CRP: C-reactive protein; GGT: Gamma glutamyl transpeptidase; INR: International normalized ratio.