The relationship between partial splenectomy and peripheral leukocyte count

Dynamic hematological changes in patients undergoing distal pancreatectomy with or without splenectomy: a population-based cohort study

Background

The clinical outcomes of patients who received distal pancreatectomy with splenectomy (DPS) and spleen-preserving distal pancreatectomy (SPDP) have been generally investigated. However, postoperative hematological changes after distal pancreatectomy with or without splenectomy are poorly understood.

Methods

Information from patients undergoing distal pancreatectomy (DP) between January 2014 and June 2019 at a single institution was reviewed. A linear mixed-effects model was used to compare dynamic hematological changes between different groups.

Results

A total of 302 patients who underwent DP were enrolled. In the long term, most postoperative hematological parameters remained significantly higher than preoperative levels in the DPS group, while postoperative lymphocyte, monocyte, basophil, and platelet levels returned to preoperative levels in the SPDP group. All postoperative hematological parameters except for red blood cell count and serum hemoglobulin level were significantly higher in the DPS group than in the SPDP group. There were no significant differences in hematological changes between the splenic vessel preservation (SVP) and Warshaw technique (WT) groups.

Conclusions

Postoperative hematological changes were significantly different between the DPS and SPDP groups. Compared to DPS, SPDP reduced abnormal hematological changes caused by splenectomy. SVP and WT were comparable in terms of postoperative hematological changes.

Trends in hematologic markers after blunt splenic trauma: Risk factor or Epiphenomenon?

BACKGROUND

Most blunt splenic injuries (BSI) are treated with nonoperative management (NOM) or embolization (EMBO). Little is known about the hematologic changes associated with these treatments. We aim to assess the temporal changes of hematologic markers in trauma patients who undergo splenectomy (SPL), packing and splenorrhaphy (P/S), EMBO, or NOM. We hypothesize that differences in trends of hematologic markers exist in patients undergoing EMBO or SPL, compared to NOM.

METHODS

An 8-year review of adult patients with BSI and underwent SPL, EMBO, P/S, or NOM. White blood cell count (WBC), hematocrit (HCT) and platelet count (PLT) at presentation to 14 days post-admission were analyzed; post-procedural complications were reviewed. Temporal trends were compared using linear mixed-effects models.

RESULTS

478 patients sustained BSI, 298 (62.3%) underwent NOM, 100 (29.2%) SPL, 42 (8.8%) EMBO, and 38 (8.0%) P/S. After adjustment for age, ISS and splenic injury grade, SPL patients had a significantly higher upward trend compared to other management strategies (p < 0.05). Infection further increased this trend. Starting on day 6, SPL patients with infections had significantly higher WBC than those without infection. SPL and P/S were more likely than NOM to develop infections after adjustment for confounders (HR = 3.64; 95%CI: 1.79-7.39 and HR = 2.59; 95%CI: 1.21-5.55, respectively). Day 6 WBC>16,000 cells/ml post-SPL had a positive predictive value (PPV) of 65.2% and negative predictive value (NPV) of 76.9% for infections. Among P/S, Day 6 WBC >10,200 cells/ml had a PPV = 50% and NPV = 86.7% for infections.

CONCLUSIONS

We observed distinct patterns of hematologic markers following BSI managed with SPL, EMBO, P/S, and NOM. Day 6 WBC increases after SPL or P/S should raise suspicion of infections and trigger a diagnostic investigation.

The role of bone marrow and spleen irradiation in the development of acute hematologic toxicity during chemoradiation for esophageal cancer

Purpose

The purpose of this study was to determine the impact of splenic and thoracic bone marrow irradiation on hematologic toxicity in the setting of chemoradiation therapy for esophageal cancer.

Methods and materials

We analyzed 60 patients with carcinoma of the distal esophagus or gastroesophageal junction who received concurrent chemoradiation in the preoperative or definitive setting. Dosimetric and volumetric parameters were calculated for the spleen, thoracic spine, and posterior ribs. The primary endpoint was grade ≥3 hematologic toxicity (HT3+). Associations were assessed using logistic and linear regression models.

Results

Twenty-one patients (35%) experienced HT3+, including 18 patients with leukopenia and 5 with thrombocytopenia. Higher spleen V5-V20 was correlated with a lower risk of HT3+ on multivariable analysis (odds ratio: 0.83 per 10 cm³ increase in V10; P = .013). A dose-dependent decrease in spleen volume was observed after radiation therapy, and a greater decrease was independently associated with a lower risk of HT3+ (odds ratio: 0.93 per 1% volume decrease; P = .014). Dosimetric parameters of the thoracic spine were not significantly associated with HT3+.

Conclusions

A greater decrease in spleen size after radiation therapy and a higher spleen V5-V20 were independently associated with a lower risk of severe hematologic toxicity. Splenic irradiation may mitigate leukopenia associated with chemoradiation therapy.

Persistent changes in circulating white blood cell populations after splenectomy

The effect of splenectomy on the incidence of infections and thromboembolisms has been investigated thoroughly. Nevertheless, the long-term effects of splenectomy on immunological profile and circulating blood counts have not been described before. To study such long-term effects, we analysed several parameters in splenectomised trauma patients and compared the results of this group ("otherwise healthy patients") to patients with a specific underlying disease. We measured platelet count, leukocytes and differential, lymphocyte subsets, serum levels of immunoglobulins, and complement pathways in 113 patients. Indications to perform a splenectomy were trauma (n = 42), Hodgkin lymphoma (n = 24), hereditary spherocytosis (n = 21), and immune thrombocytopenia (n = 26). In trauma patients lymphocytes and lymphocytes subsets were particularly elevated compared to normal population values. Splenectomised patients with Hodgkin lymphoma had significant lower numbers of T lymphocytes than trauma patients. Significant increases in platelets, leukocytes, and monocytes were observed in patients with hereditary spherocytosis. Occurrence of MBL genotype was different in ITP patients than in other splenectomised groups and the normal population. In splenectomised patients (> 4 years), platelet counts and lymphocyte subsets are increased which persist over time. As a result, these blood counts in splenectomised patients differ from reference values in the normal population.

Adoptive transfer of immune subsets prior to MCAO does not exacerbate stroke outcome in splenectomized mice

The peripheral immune response contributes to neurologic impairment after stroke and the extent of initial damage is greater in males than females. We have previously shown that spleen cells directly contribute to ischemic damage in males, as splenectomy prior to experimental stroke eliminates the sex differences in infarct volume. This study aims to determine which specific subset of immune cells exert pathogenic effects when injected 24 hours before MCAO induction into splenectomized male and female WT mice. The results demonstrate that CD4/CD8/CD11b treated mice had no significant effect on infarct volumes vs. vehicle-treated control mice after MCAO. However, there were significant alterations to the resident peripheral immune composition. These results suggest that there are regulatory factors resulting from splenectomy or other possible influences that inhibit peripheral immune cell contribution to neuroinflammation and thus contributing to differential effects of the spleen on stroke outcome in males and female mice.

Splenectomy increases mortality in murine Trypanosoma cruzi infection

The spleen is a secondary lymphoid organ that harbours a variety of cells such as T and B lymphocytes and antigen-presenting cells important to immune response development. In this study, we evaluated the impact of spleen removal in the immune response to experimental Trypanosoma cruzi infection. C57BL/6 mice were infected with Y strain of the parasite and infection was followed daily. Mice that underwent splenectomy had fewer parasites in peripheral blood at the peak of infection; however, mortality was increased. Histological analysis of heart and liver tissues revealed an increased number of parasites and inflammatory infiltrates at these sites. Spleen removal was associated with reduction in IFN-γ and TNF-α production during infection as well as with a decrease in specific antibody secretion. Haematological disorders were also detected. Splenectomized mice exhibited severe anaemia and decreased bone marrow cell numbers. Our results indicate that spleen integrity is critical in T. cruzi infection for the immune response against the parasite, as well as for the control of bone marrow haematological function.