Splenic abscess: treatment options in a disease with high mortality

Abstract

Background

Spleen abscess is a rare and serious condition. Splenectomy and imaging-guided percutaneous catheter drainage (PCD) are the methods used in the treatment, but there is still a debate about the appropriate treatment for the patient.

Methods

The results of 16 patients treated for spleen abscesses in our clinic between 2012 and 2021 were reviewed. The patients were divided into two groups according to splenectomy and PCD.

Results

In the study, PCD was performed in 11 patients (68.75%), but three of these patients required splenectomy due to inadequate drainage. The patients who underwent splenectomy were significantly younger than the patients who underwent PCD (p < 0.05). One patient underwent PCD and 2 patients underwent splenectomy after PCD died.

Conclusion

Spleen abscess is a serious clinical picture that requires a multidisciplinary approach and is life-threatening. New clinical studies are needed for a treatment algorithm that will provide good results.

Introduction

Spleen abscess(SA) is a life-threatening rarely seen disease (0.14–0.7%) [1, 2] Also, it is so difficult to detect that it becomes a diagnostic challenge. Meanwhile, it carries a high risk of mortality when untreated [3, 4]. Trauma, infective endocarditis, immunodeficiency states, diabetes mellitus, malignancies, and systemic infections may play a role in the etiology of spleen abscess [5–9]. Hospitalization is recommended for all patients with spleen abscesses [5–7, 10]. Intravenous antibiotics, percutaneous catheter drainage(PCD), and surgery are the treatment modalities that can be used in the management of splenic abscesses. The recommended treatment for splenic abscess is splenectomy; but lately, PCD instead of splenectomy is preferred in the treatment of splenic abscess for preserving the immunologic function of the spleen [11]. The spleen plays an important role in the phagocytosis of encapsulated bacteria; after total splenectomy, the lifetime risk of overwhelming post-splenectomy infection (OPSI) may be as high as 5% and it may even prove fatal [6].

This study aims to evaluate the effectiveness and results of treatment modalities in the management of splenic abscesses.

Materials and methods

Patients diagnosed with non-parasitic SA at the University of Health Science, Turkey, Haydarpasa Numune Training and Research Hospital, between April 2012 and April 2021 were retrospectively evaluated. Inclusion criteria were determined as; 1- Being over 18 years of age, 2- Patients with radiological or pathologically reported splenic abscess, 3- Patients who were followed up and treated in our clinic. Exclusion criteria were determined as; Being under 18 years of age. All patients who were followed up in our clinic were included in the study. Demographic features, clinical symptoms and signs, blood analysis, diagnostic imaging methods, and co-morbidity of patients were evaluated (Figs. 1 and 2). Bacteriologic analyses were performed. In our study, percutaneous catheter drainage was performed by placing an 8 French (F) or 10 F catheter into the abscess site using the Seldinger method under USG imaging [12]. Open splenectomy was performed in patients who underwent surgery. Outcome information such as treatment modality, length of hospital stay, and mortality were obtained from hospital records.

Fig. 1.

CT image of spleen abscess, respectively, diagnosed CT, control CT after catheterisation and control CT after treatment. Splenic abscess sites are shown with red arrows

Fig. 2.

MRI image of spleen abscess. Splenic abscess sites are shown with red arrows

Statistically analysis

While evaluating the findings obtained in the study, IBM SPSS Statistics 26 (IBM SPSS, Turkey) program was used for statistical analysis. Descriptive statistical methods were used while evaluating the study data. Mann-Whitney U test was used for the comparison of two groups of data that did not show normal distribution. Friedman test was used to evaluate the follow-up of variables that did not show normal distribution. Significance was evaluated at the p < 0.05 level at least.

Results

Our study consisted of a total of 16 patients, 5 (31.3%) of whom underwent splenectomy, 8 (50%) underwent PCD, and 3 (18.7%) underwent splenectomy after PCD. The ages of the patients ranged from 22 to 78, with a median of 59.

As co-morbidities, heart valve disease, and diabetes were present in 5 (31.3%) patients. No significant co-morbidities were observed in 6 (37.5%) patients. As main symptoms and signs, pain, and fever were observed in 11 (68.8%) and in 7 (43.8%) patients respectively (Table 1).

Table 1.

Patient’s demographics features, co-morbidities and symptoms/signs

Patient Number	AGE	GENDER	Co-morbidities	Symptoms/Signs	WBC(10*3 µl)	NEUT(10*3 µl)	CRP(mg/dL)
1	75	M	HT, HVD, AF	Pain	10.86	9.6	231.56
2	39	M	-	---	17.7	15.5	3.81
3	52	F	-	---	10.1	8.75	14
4	41	F	HT, HVD, AF	Pain, fever	21	18.9	4.02
5	34	F	Obesity, Sleeve Gastrectomy	Pain	4.36	3.84	17.87
6	54	M	Gastric cancer	---	2.88	1.9	22.72
7	22	M	---	Pain, fever	19.8	16.1	-
8	78	F	DM	Pain, fever	11.11	10.02	37.5
9	62	M	DM	---	18.82	17.62	19
10	68	F	DM, IE, CRF, CHF	Pain, fever	11.18	9.79	63.82
11	67	M	IE, Pemphygus	---	8.03	6.59	99.64
12	75	M	DM, IE, HT	Pain, fever	11.23	10.48	17.8
13	56	M	DM, HT, CABG	Pain	19.03	17.5	16.4
14	23	M	-	Pain, fever	9.3	8.11	8.4
15	63	M	-	Pain, fever	30.88	27.3	9.1
16	63	M	-	Pain	18.2	17.1	24.5

WBC: white blood cell, NEUT: Neutrophil, CRP: C-reactive protein, M:male, F:female, DM: diabetes mellitus, IE: infective endocarditis, HT: hypertension, CRF: chronic renal failure, CHF: chronic heart failure, CABG: coronary artery bypass graft, HVD: heart valve disease, AF: atrial fibrillation

The median white blood cell (WBC) value of patients who underwent splenectomy was 17,700 µL (4360–21000), and the median WBC value of patients who underwent PCD was 11,180 µL (2880–30880). No statistically significant difference was found between the WBC values of the two groups(p > 0.05).

Abdominal ultrasonography and CT were done on all patients. The size of the abscess was a median 90 mm (range 27 and 155 mm). While 13(%81) patients had unilocular abscesses, 3(%19) patients had 2-focal abscesses. There were no cases with more than three foci identified in the radiological examinations.

Microorganisms were identified in 5 patients (31%), with E.coli in 4 and Salmonella in 1 patient.

As a first-line treatment, PCD was performed in 11 (68,75%) of patients under ultrasound-guided at mean 4th (1–14 days) days of admission. The splenic abscess was aspirated via 8–10 F catheter, cavity lavage (washing) with saline, catheter in the cavity for mean 8th days (1–20 days), daily lavage, and aspiration. Finally, the catheter was withdrawn on the mean 8th days (2–20 days) after healing control with ultrasound.

After insufficient PCD on three (18.8%) patients, splenectomy was performed as a second-line procedure (Table 2). In patients who underwent splenectomy, open total splenectomy was performed. Intensive care (ICU) was needed in 2 (13.3%) patients. Mortality occurred in three (18.8%) male patients. Patient number 1 underwent PCD on the 4th day of hospitalization and was transferred from ICU to the ward. During follow-up, 7 days later, the catheter was blocked and signs of sepsis were observed in the patient and the catheter was changed. However, since the patient’s general condition did not improve and the content of the catheter was too solid to drain, an operation decision was made and the patient was transferred to the postoperative ICU. Despite supportive treatments, the patient’s general condition did not improve and cardiac arrest developed and the patient died.Patient number 6 died due to bleeding from stomach cancer. The endoscopic intervention could not stop the bleeding. Patient number 12 had a catheter inserted on the first day of his hospitalization, and the day after the procedure, the patient developed sudden cardiac arrest during ward follow-up. The patient, who returned to life after cardiopulmonary resuscitation, was transferred to the ICU, but died on the same day despite supportive treatment. Patient number 1 was accepted as having died due to septic shock. The development of cardiac arrest in patient number 12 while his vital signs were stable and the patient’s very rapid mortality suggested that the cause of death was a cardiac arrest due to IE.

Table 2.

Managements of patients and outcomes

Patient Number	Abscess size (mm)	Drainage	Splenectomy	Culture	Antibiotics	ICU	Mortality
P9	103	+		E. Coli	Piperacilline/Tazobactame, Metronidazole
P10	95	+		E. Coli	Ampicilline/Sulbactame
P11	60	+			Ceftriaxone, Metronidazole
P12	100	+			Ampicilline	+	M
P13	110 and 15	+			Ceftriaxone, Metronidazole
P14	90	+			----
P15	155	+		Salmonella	Meropenem/Teicoplanine
P16	45	+			Ceftriaxone, Metronidazole/Ertapenem
P2	55 and 22		+		Ceftriaxone
P3	150		+		Ceftriaxone, Metronidazole
P4	70		+		-----
P5	27		+		Cefepime/Vancomycine, Metronidazole
P7			+		----
P1	115	+	+	E. Coli	Meropenem, Vancomycin, Polymixine	+	M
P6	70	+	+		Ceftriaxone, Metronidazole		M
P8	57 and 15	+	+	E. Coli	Ampicilline/Sulbactame, Piperacilline/Tazobactame,

E.coli: Escherichia coli, ICU: Intensive Care Unit, M:mortality

The age of the patient group who underwent percutaneous drainage was found to be higher than the splenectomy group (p < 0.01). Splenectomy was performed in 5 (31.3%) patients on mean 4th days (range 1–11 days) of admission as a first-line treatment. The median length of hospital stay was 16 (range 3 and 53) days. There was no statistically significant difference in the rates of intensive care admission and mortality in patients who underwent splenectomy or PCD (p > 0.05). Abscess size was not found to be effective in the choice of splenectomy or PCD in our study. (p > 0.05) Splenectomy or PCD did not affect the length of hospital stay of the cases. (Table 3)

Table 3.

Evaluation of descriptive features according to treatment

		Invasive Treatment		p
		Splenectomy (n = 5; %31.3)	PCD (n = 11; %68.7)
		n (%)	n (%)
Age (year)	Median (Min-Max)	39 (22–52)	63 (23–78)	a0,008**
Sex	Female	3 (60,0)	2 (18,2)	b0,245
	Male	2 (40,0)	9 (81,8)
HVD	No	4 (80,0)	7 (63,6)	b1,000
	Yes	1 (20,0)	4 (36,4)
DM	No	5 (100)	6 (54,5)	b0,119
	Yes	0 (0)	5 (45,5)
Pain	No	2 (40,0)	3 (27,3)	b1,000
	Yes	3 (60,0)	8 (72,7)
Fever	No	3 (60,0)	6 (54,5)	b1,000
	Yes	2 (40,0)	5 (45,5)
ICU ( n  = 15)	No	5 (100)	8 (80,0)	b0,524
	Yes	0 (0)	2 (20,0)
Mortality	No	5 (100)	8 (72,7)	b0,509
	Yes	0 (0)	3 (27,3)
Abscess Size (cm)	Median (Min-Max)	6,25 (2,7–15)	9,5 (4,5–15,5)	a0,327
Length of stay (Day)	Median (Min-Max)	12 (4–32)	17 (3–53)	a0,461

^aMann Whitney U Test ^bFisher’s Exact Test **p < 0,01

^{PCD: Percutaneous Catheter Drainage, HVD: Heart Valve Disease, DM: Diabetes Mellitus, ICU: Intensive Care Unit}

Discussion

A SA is an unusual but potentially life-threatening illness if not promptly identified and treated. The mortality rates vary, range 12.4–27.6% [4, 13]. This study aims to evaluate the clinical approach and outcome of spleen abscess. The mortality rate is found to be 18.8% in this study. In another study, the mortality of splenic abscess was reported to be 100% if left untreated [14].

In our study, the median age was 59 (range 22–78). In a study similar to ours of 25 patients, the mean age of all patients (± SD) was 48.64 ± 19.08 years (18–88 years) [15]. In another study of 18 patients, the mean patient age was 47.2 [16].

SA are manifested with nonspecific symptoms. Fever and pain are the most common symptoms [13, 15, 17]. In our patients, pain was the most common presenting symptom (68.8%) and the second symptom was fever (43.8%).

High WBC, C-reactive protein (CRP) and procalcitonin levels in the blood can guide us in the presence of infection and in the evaluation of response to treatment in splenic abscesses [18]. In addition, a decrease in butyryl cholinesterase values ​​has been associated with infection in a recent prospective study [19]. However, the contribution of infectious parameters to the management of these cases in the follow-up of SA patients has not been adequately evaluated in the literature. In our study, similar to the literature, the clinical status of the patients and radiological imaging were at the forefront rather than blood markers.

The diagnosis of splenic abscess requires noninvasive imaging; CT is the preferred method for diagnosis but, the diagnosis can also be made by ultrasonography [11, 16]. Typically, a well-circumscribed hypodense collection with an enhancing rim was seen on CT. We did abdominal CT and ultrasound on all patients.

Approximately 70% of splenic abscesses result from the hematogenous spread of the infective organism from another location, especially in endocarditis and osteomyelitis [20–22]. In a study in the literature, it was reported that the most common site of embolism in patients who underwent cardiac surgery due to infective endocarditis was the spleen [22]. Splenic embolism may cause infarction, rupture, and rarely abscess in the spleen. Before valve surgery, splenectomy is often recommended due to fear of persistent bacteremia and reinfection of the new valve. The patient’s condition is important in the choice of treatment modalities, when a major abdominal operation is contraindicated or less invasive measures are preferred, anti-biotherapy and PCD of the abscess are other alternatives. Three patients with SA had infective endocarditis in this study, because of the significant systemic problems of patients, PCD was preferred.

The median hospital stay of our patients was 16 days (3–53).In a study of 75 patients, the mean hospital stay of patients who underwent PCD and splenectomy was 11.42 and 15.58 days, respectively [23].

In our study, the overall mortality rate was 3/16 (18.8%). The highest mortality rate reported in the case series reported in the literature is 12/67 (17.9%)5. The mortality rate in the meta-analysis was 64/589 (10.8%)24. In our series, no statistically significant difference was observed in terms of mortality between the splenectomy group and the PCD group. The highest reported mortality rate among patients undergoing splenectomy was 7.7%, while this rate was reported as 12% in the meta-analysis [5, 24]. The highest reported mortality rate in patients undergoing PCD was 40%, while it was reported as 8% in the meta-analysis [4, 24]. (Table 4).

Table 4.

Studies on splenic abscess in the literature

Study	Study Type	Number of patients	PCD(%mortality)	Splenectomy(%mortality)	Mortality(%)
Gutama et al(2022)24	Meta-Analysis	589	301(%8)	288(%12)	64(%10.8)
Khan et al(2022)15	Retrospcetive	25	15(%20)	2(%0)	3(%12)
Shetty et al(2016)17	Retrospective	9	3(%0)	Parsiyel Splenectomy(1)(%0)	0(%0)
Singh et al(2021)3	Retrospective	36	24(%8.3)	6(%0)	5(%13.9)
Liu et al(2014)4	Retrospective	24	5(%40)	5(%0)	4(%14.3)
Chang et al(2006)5	Retrospective	67	21(%28.6)	26(%7.7)	12(17.9)
Lee et al(2018)13	Prospective observational	16	4(%0)	1(%0)	2(%12.5)
Z.Hasan et al(2020)20	Retrospective	10	-	5	-
Lee et al(2011)16	Retrospective	18	4	6	4(%16.6)
Sreekar et al. (2011)23	Retrospective	75	19(%0.05)	42(%4.76)	5(%0.066)

In our literature review, the place of only IV antibiotic therapy in splenic abscess is quite confusing. In a single-center study performed in Qatar and another study conducted in Taiwan, no difference in mortality was observed between IV antibiotic therapy and invasive procedures [5, 15]. A study performed in Taiwan in 2018 associated only IV antibiotic therapy with high mortality [13]. In the study by Liu et al., survival of patients treated with only IV antibiotics was found to be higher [4].

For the treatment of SA, a case-specific treatment modality should be chosen. PCD is particularly effective for patients who are poor candidates for surgery [10]. One of the advantages of PCD is to protect the spleen. Another advantage is that it provides source control, causes fewer complications during the operation, and provides faster recovery time [3, 10, 15, 17, 25]. In this study, PCD is preferred in ten patients but in two patients who have multilocular lesions according to incomplete resolution after drainage, splenectomy is performed. It was possible to treat unilocular lesions often with PCD along with antibiotics.

In a meta-analysis,46 retrospective studies were evaluated, they did not find a statistically significant difference between mortality and complications in patients with SA treated with splenectomy versus PCD [24].

On the other hand abscess characteristic plays an important role in the choice of treatment modality. Splenectomy can be performed for all abscess types including small, large, uni, or multilocular but the size of the abscess, whether it is uni or multilocular, affects the success of percutaneous drainage [24]. In our study, PCD was performed with an 8 F catheter in 3 of our mortal patients. The relationship between catheter size and mortality could not be analyzed statistically due to the small number of patients. Splenectomy is required in patients for whom PCD is not effective. In appropriate cases, laparoscopic or conventional partial splenectomy can be performed to preserve the immune functions of the spleen. De Pastena et al. reported that laparoscopic partial splenectomy can be safely performed in the treatment of a splenic abscess [26].

Our literature search shows that with the widespread use of obesity surgery, the complication of splenic abscess due to surgery has increased [27]. In particular, the management of splenic abscesses due to IE is an important health problem and is mentioned in the sections requiring evidence in the IE guideline [28].

Considering all these, we wanted to present you with a summary of our own management algorithm so that it can be on the agenda of prospective studies and consensus meetings to better manage SA cases in the future.

Our recommendations for SA management;

1. We recommend that all patients receive blood cultures and, if possible, abscess cultures, and that extended-term antibiotic therapy be initiated and treatment be reviewed according to the antibiogram results. (Evidence Level C)

2. In patients with valve involvement due to IE, we request that splenectomy or PCD be chosen in cooperation with the Cardiovascular Surgery team in order to prevent systemic complications. (Evidence Level C)

3. We recommend drainage under appropriate conditions for patients with SA. If PCD is not appropriate, we recommend that minimally invasive approaches be the first choice. (Evidence Level C)

4. If successful drainage cannot be achieved with PCD or other spleen-protecting methods, we find it safe to perform splenectomy without compromising the patient’s general condition. (Evidence Level C)

The small number of patients, the retrospective and single-center nature of our study, and the lack of consultation and joint decision-making between disciplines when selecting the treatment plan are important limitations of our study. It was thought that the spleen abscess should be managed by a multidisciplinary team including a general surgeon, an infectious diseases physician, an interventional radiologist, and an intensive care physician. A statistically significant cause for mortality or a marker showing prognosis could not be found.

Conclusion

In the management of spleen abscesses, patients should be evaluated in a multidisciplinary manner. In splenic abscess, a patient-specific antibiotic therapy, drainage and surgical operation plan should be drawn. Patients should be followed very closely. Prospective studies with a high level of evidence are needed to determine patient-based mortality reduction algorithms in treatment management.

Author contributions

KÇ and MGG designed the methodology and wrote the main text.AA performed data preparation and literature review. All authors reviewed the manuscript.

Funding

No funding was used for the research.

Data availability

No datasets were generated or analysed during the current study.

Declarations

Ethics approval

This study was approved by the Haydarpaşa Numune Training and Research Hospital Medical Specialization Education Board (TUEK) local ethics committee (E-62977267-771-218261334) and approval date 25.10.2022. Our study was designed retrospectively in accordance with the Declaration of Helsinki. Informed consent was obtained from the patients at the time of hospitalization.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.