Pneumococcal serum opsonizing activity in splenectomized children

Autoinfarcted wandering spleen and fatal pneumococcal sepsis in an infant

A wandering or ectopic spleen, a rare congenital condition caused by improper fixation of the ligamentous attachments, was identified during a postmortem examination of a 10-month-old female who had died of Streptococcus pneumoniae sepsis. The wandering spleen was autoinfarcted and adherent to the left hepatic lobe, with resultant functional hyposplenism.

Aderência e atividade microbicida de monócitos em portadores de esquistossomose mansônica na forma hepatoesplênica cirúrgica

A cirurgia nas crianças portadoras de esquistossomose mansônica inclui esplenectomia, ligadura da veia gástrica esquerda e o auto-implante de tecido esplênico no omento maior. A eficácia desse procedimento pode ser responsável pelo desaparecimento da sepse fulminante pós-esplenectomia (SFPE) neste tipo de paciente. Esta condição é atribuída à diminuição de IgM, de linfócitos circulantes, de properdina e ausência de tuftsina, o que conduz a deficiência da atividade das células macrófágicas, que são responsáveis pela aderência à bactéria, fagocitose e destruição das mesmas. OBJETIVO: Analisar os aspectos funcionais dos monócitos destes pacientes, operados quando crianças, no Serviço de Cirurgia Geral da Criança do Hospital das Clínicas da UFPE, entre 1991 a 2000. MÉTODOS: Foram analisados os índices de aderência in vitro dos monócitos e a geração do ânion superóxido (O2-), em três grupos. O 1º, auto-implante (AI), constituído por 18 portadores de esquistossomose mansônica na forma hepatoesplênica, submetidos a esplenectomia, ligadura da veia gástrica esquerda e auto-implante de tecido esplênico no omento maior; o 2º, (ESP), formado por nove pacientes similares, submetidos a esplenectomia e desconexão ázigo-portal, e o 3º,(CT), constituído por 12 adolescentes sadios, oriundos da mesma condição sócio-econômica-geográfica. RESULTADOS: Não houve diferença no índice de aderência entre os três grupos. Os monócitos dos pacientes do grupo AI tiveram a geração de O2- semelhante à dos indivíduos do grupo CT, e significantemente maior do que os pacientes do grupo ESP. CONCLUSÕES: Os monócitos dos portadores de esquistossomose hepatoesplênica submetidos a esplenectomia, ligadura da veia gástrica esquerda e auto-implante de tecido esplênico no omento maior se mostram funcionalmente similares aos de indivíduos normais da mesma condição sócio-econômica-geográfica.

Current concepts in splenic trauma

Despite its protected location inside the rib cage, the spleen remains the most commonly injured organ after blunt abdominal trauma. The clinical decision-making process of splenic injury management continues to evolve due to improvements in surgical technique and noninvasive assessment. Splenic preservation techniques and splenic injury grading systems using computerized tomography were developed due to an increased understanding of the spleen's importance in the body's immunological defense system and awareness of the spleen's resiliency after injury. The concept of splenic salvage using splenorrhaphy and nonoperative management was initially applied to the pediatric population during the 1970s, with great success. Application of splenic salvage to hemodynamically stable adult patients with known or unknown splenic injury has demonstrated that adults can be less predictable in their clinical course. Despite the rigorous attention splenic trauma has received, it remains a controversial subject in the surgical and the radiological literature.

Reduced levels of CD2+ cells and T-cell subsets in patients with sickle cell anaemia

Investigation of B lymphocytes and T-lymphocyte subsets in patients with homozygous sickle cell disease (SCD) who were not in crisis and who did not demonstrate infectious complications showed these cell populations to be abnormal. The proportion of total T cells (CD2+) was significantly reduced (P = 0.002) when compared with controls. B cells (CD19+) were significantly elevated in sicklers (P = 0.029). Helper/inducer (CD4+) and suppressor/cytotoxic (CD8+) cells were significantly reduced (P = 0.019 and P = 0.0001, respectively). The average ratio of T cells/B cells in SCD patients was 3.7:1, while controls showed a ratio of 7.2:1. Since patients with SCD are abnormally susceptible to severe infections, we discussed the implications of low levels of CD4+ and CD8+ cells and the consequent cytokine imbalance in SCD patients which may lead to impairment of immunity.

Splenectomy does not correlate with length of survival in patients undergoing curative total gastrectomy for gastric carcinoma. Univariate and multivariate analyses

The relationship between splenectomy and survival time after curative total gastrectomy for advanced gastric cancer was examined by reviewing retrospectively data on 252 patients treated in our clinics between 1965 and 1985. One hundred three patients (40.9%) did not undergo splenectomy and 149 (59.1%) did. In patients subjected to splenectomy, advanced stages of the malignancy were more frequent and metastasis was noticed in 8.1% of splenic hilar lymph nodes and in 10.1% of the lymph nodes associated with the splenic artery. A univariate analysis revealed that the survival time of patients with splenectomy was significantly less than those for whom splenectomy was not done (P less than 0.05). In a subgroup of our patients stratified to adjust for the stage of disease, there was no significant difference between the survival rates. Subsequently, multivariate analysis using the Cox regression analysis adjusted for sex, age, and other covariates indicated that serosa invasion, lymph node metastasis, and tumor size were the most important prognostic factors, and there was no correlation whatever with splenectomy. Our findings rule out any relationship between splenectomy and length of survival time in patients undergoing curative total gastrectomy for advanced gastric cancer.

Splenectomy does not correlate with length of survival in patients undergoing curative total gastrectomy for gastric carcinoma. Univariate and multivariate analyses

The relationship between splenectomy and survival time after curative total gastrectomy for advanced gastric cancer was examined by reviewing retrospectively data on 252 patients treated in our clinics between 1965 and 1985. One hundred three patients (40.9%) did not undergo splenectomy and 149 (59.1%) did. In patients subjected to splenectomy, advanced stages of the malignancy were more frequent and metastasis was noticed in 8.1% of splenic hilar lymph nodes and in 10.1% of the lymph nodes associated with the splenic artery. A univariate analysis revealed that the survival time of patients with splenectomy was significantly less than those for whom splenectomy was not done (P less than 0.05). In a subgroup of our patients stratified to adjust for the stage of disease, there was no significant difference between the survival rates. Subsequently, multivariate analysis using the Cox regression analysis adjusted for sex, age, and other covariates indicated that serosa invasion, lymph node metastasis, and tumor size were the most important prognostic factors, and there was no correlation whatever with splenectomy. Our findings rule out any relationship between splenectomy and length of survival time in patients undergoing curative total gastrectomy for advanced gastric cancer.

Humoral immune response to pneumococcal antigen 23-F in an asplenic patient with recurrent fulminant pneumococcaemia

Host defence mechanisms were analysed in a patient with three episodes of fulminant pneumococcaemia and one episode of bacteraemic epiglottitis with Haemophilus influenzae type b. The first episode took place 11 years after splenectomy for blunt abdominal trauma. Investigations revealed several host defence mechanisms to be impaired. In addition to the patient's asplenia, an inherited C2-deficiency was noted. Assessment of IgG subclasses repeatedly revealed markedly low IgG4 concentrations. These were not due to an increased turnover of IgG4, as could be shown following infusion of intravenous IgG. In addition, IgG2 concentrations were low in the patient who lacked G2M(23). Opsonic mediating antibodies against type 23-F pneumococci were in the range of those of non-immune volunteers 6 months after vaccination with a 23-valent pneumococcal vaccine. These antibodies did not increase after a septic episode with 23-F capsular-type pneumococci. Neutrophil function was apparently normal.

Postsplenectomy sepsis

This review examines the infectious consequences of elective and emergency splenectomy, highlighting the importance of infection with Streptococcus pneumoniae. The influence of splenectomy on the immune system is discussed and the efficacy of vaccines in preventing postsplenectomy sepsis is reviewed. The value of alternative methods of preventing postsplenectomy sepsis is considered.

Effect of splenectomy on gram-negative bacterial clearance in the presence and absence of sepsis

Severe sepsis leads to depression of the reticulo-endothelial system (RES) with delayed bloodstream clearance of particulate matter and bacteria. Splenectomy results in increased susceptibility to infection with encapsulated organisms but its effect on the resistance to postoperative Gram-negative infection has been little studied. We have investigated the effect of splenectomy on RES function by measurement of plasma fibronectin concentrations and bacterial clearance in the presence and absence of sepsis. In experiment 1, rabbits underwent splenectomy (n = 8) or laparotomy only (n = 8) 4 weeks before a second laparotomy. In experiment 2, animals had either splenectomy (n = 8) or laparotomy only (n = 8) followed 4 weeks later by devascularization of the appendix (sepsis). Plasma fibronectin concentrations and the blood clearance and organ distribution of an intravenous injection of 75Se-labelled viable Escherichia coli (2-3 X 10(8) colony forming units (c.f.u.] were measured 24 h after the second operation. Splenectomy resulted in: (1) a persistent reduction in plasma fibronectin concentration in the presence and absence of sepsis, and (2) a delay in the bloodstream clearance with reduced hepatic (Kupffer cell) uptake of E. coli which was exaggerated in the septic splenectomized animal. It is concluded that the spleen may be important for Gram-negative bacterial clearance, possibly related to its influence on plasma fibronectin concentration and Kupffer cell function.

Splenic function: physiology and splenic hypofunction

A wide variety of disorders can result in diminished splenic function. The pathophysiology appears to be clearly defined in some instances, such as congenital asplenia and disorders of splenic vascular obstruction or congestion. In others, such as the autoimmune and GI disorders, the mechanism remains poorly defined. Further research is needed. The hyposplenia which occurs in many of these disorders has been associated with an increased risk of life-threatening, overwhelming bacterial sepsis. In other instances, this complication has not been reported. This certainly should not be interpreted to mean that it cannot occur. The risk of septicemia in hyposplenic disorders is rarely above 10 to 15%. In disorders with minimal inhibition of splenic function, the incidence of sepsis would presumably be less than the 1.5% incidence following surgical splenectomy for trauma. Considering these data, a very large number of patients would have to become asplenic before it would be likely that one would develop sepsis. Furthermore, the lack of awareness of the possibility of hyposplenia-related sepsis in many of these disorders may cause such occurrences to go unrecognized. Finally, since the risk of sepsis is probably less in hyposplenic adults as compared to children, studies on adults may underestimate the incidence of this complication in children. Many of the disorders reported to cause hyposplenia in adults have not been noted to do so in children. In instances such as celiac disease, it may take many years for the complication to manifest so that it would be unlikely for a child to manifest hyposplenia during childhood. However, in other instances, not enough children have been studied to be confident that the hyposplenia and its associated risk of sepsis are not complications that occur in children. Hyposplenia-related bacterial septicemia is a catastrophic complication. If a patient develops a disorder that is potentially associated with hyposplenia, the patient should be observed for signs of asplenia in the peripheral blood. If the technique is available, quantitation of red cell pits should be performed. If not, other studies of splenic function such as radionuclide scans should be considered, depending on the incidence of hyposplenia in that particular disorder. If evidence of asplenia develops, pneumococcal vaccine should be administered, penicillin prophylaxis should be considered, significant febrile episodes should be managed aggressively, and probably most importantly, the patient and family should be carefully educated about this complication. Most deaths from hyposplenia-related septicemia are preventable.

Methods of splenic preservation and their effect on clearance of pneumococcal bacteremia

The intravascular clearance of type 3 Streptococcus pneumoniae was studied in Sprague-Dawley rats. Sham celiotomy was performed on 20 animals while another 20 rats underwent splenectomy. Four weeks later, bacteremia was induced by intraperitoneal (IP) injection of S. pneumoniae. Serial cultures of peripheral blood were obtained. Splenectomy produced significant impairment of intravascular clearance of bacteria compared to that noted among control animals (p less than 0.01). Eighty animals were divided into four equal groups: I--splenectomy, II--50% splenectomy with the upper half left in situ connected to the short gastric vessels, III--50% splenectomy with the lower half left in situ connected to the hilar vessels, and IV--splenectomy with implantation of splenic fragments. Pneumococcus was administered IP 16 weeks later. Rats were killed 6 hours after bacterial challenge. Residual splenic tissue was weighed. There was significantly less splenic tissue in Groups II-IV than noted in sham animals after 16 weeks (p less than 0.01). The type of partial splenectomy did not significantly affect the weight of residual splenic tissue 16 weeks later. Implantation did yield viable splenic tissue, though the amount proved significantly less than that resulting from either type of partial splenectomy (p less than 0.01). Mean bacterial counts with time for short gastric (Group II) and hilar (Group III) remnant animals were significantly different from those for the asplenic (Group I) rats (p less than 0.02 and p less than 0.001, respectively). Animals with splenic implants (Group IV) were not significantly different from asplenic rats (Group I). Animals with hilar splenic remnants proved significantly different from those with short gastric splenic remnants (p less than 0.01). Partial splenectomy offers protection against pneumococcal bacteremia, though preservation of the hilar blood supply affords the most benefit. The utility of splenic implantation remains unproven.

Surgical diseases of the spleen

Recognition of the spleen's important immune function has led to a more conservative surgical approach to the spleen. This has proved to be both safe and beneficial to the patient.

Defective activation of neutrophils after splenectomy

Neutrophil chemotaxis and phagocytosis in the presence of serum from 20 patients who had undergone splenectomy and from 15 healthy volunteers was studied. The mean distance migrated by normal neutrophils in the presence of serum from the patients after splenectomy was significantly less than that when normal serum was used (p less than 0.005). The percentage of neutrophils phagocytosing a yeast was also significantly reduced in the presence of serum from patients after splenectomy (p less than 0.02). In addition, when neutrophils from these patients were studied both chemotaxis and phagocytosis were enhanced in normal compared with autologous serum (p less than 0.05).

Immunological consequences of splenectomy

A series of reports have dealt with the occurrence of overwhelming infections in splenectomized patients. Being the largest individual organ of the phagocytic apparatus, the spleen is responsible for the phagocytosis of insufficiently opsonized particles. These are taken up by macrophages, processed, and expressed, together with determinants of the HLA system, on the membrane of the macrophage. T cells recognize these structures and proliferate in response, thus inducing a series of immunoregulatory mechanisms. The anatomic design of the spleen allows for close contact between macrophages and T cells. Thus, splenectomy represents a major intervention into the immunologic system. Splenectomized patients have been shown to have low concentrations of IgM, decreased production of antibodies directed against pneumococci and Escherichia coli, and several defects in cellular immune function, including decreased numbers of T cells and a reduction in lymphocyte proliferative responses. Thus, the removal of the spleen affects certain immunological reactions, which are reflected by a number of clinical findings.

Complement studies in splenectomized patients

Total haemolytic complement activity, C2, C5, total alternative pathway activity, factor B, and C3d were measured in 85 splenectomized patients from 1 month to 32 years after splenectomy. Furthermore the patients were investigated for circulating immune complexes. No major deficiencies of the complement factors were detected. In a few patients a reduced C2 level was caused by genetically determined defects or was due to complement consumption in conjunction with circulating immune complexes. The complement levels were normal in 2 patients who had survived overwhelming infections after splenectomy. C5 was elevated in a major proportion of the patients, and it is suggested that this might be caused by post-splenectomy monocytosis. Circulating immune complexes were found in 20% of all cases, irrespective of the presence of residual splenic tissue. Thus the commonly cited impairment of the complement system after splenectomy does not seem to be substantiated, and the deficient resistance against bacterial infections in splenectomized patients does not seem to include abnormalities of the complement system.

Late infections following splenectomy in Hodgkin's disease

Here 145 reported post-splenectomy infections in 115 patients with Hodgkin's disease are reviewed. Such infections can occur at any age (median age 19.8 years) and the interval from splenectomy to the infection is quite variable (median 21.9 months). Most infections are present clinically as pneumonia, septicemia, meningitis, or a combination thereof, with the most common offending organism being pneumococcus. The infection can be fulminant and even fatal. It is recommended that the spleen should only be removed when essential. A staging laparotomy and splenectomy seem justifiable only in cases of Hodgkin's disease where a change of staging would lead to a change of planned therapy. Prophylactic penicillin should be administered at least for 3 years and possibly indefinitely since post-splenectomy infections can occur many years later. Pneumococcal vaccine should also be given before any chemotherapy or radiotherapy is initiated. Prompt and aggressive treatment should be given when post-splenectomy infection is diagnosed.

Antibody response and opsonization afer pneumococcal vaccination in splenectomized children and healthy persons

A significant rise in antibody against pneumococcal types 3, 6A and 25 after pneumococcal vaccination could be demonstrated in 26 of 30 individuals (87%) using an enzyme-linked immunosorbent assay. Similar geometric mean antibody fold increases were found in splenectomized children, non-splenectomized children and healthy adults for types 6A and 25. Splenectomized children exhibited a somewhat lower, but not statistically significant, geometric mean antibody fold increase against type 3 (p = 0.10), as compared to non-splenectomized children. For the whole group a negative correlation could be demonstrated between prevaccination antibody concentration and antibody fold increase after vaccination. After vaccination an enhanced serum opsonic activity against type 3 was found by granulocyte glucose-l-14C oxidation for the whole group of 30 patients (p less than 0.05) but nine individual patients (30%) failed to exhibit an increase. No differences between the three patient groups were demonstrable. Changes in serum opsonic activity could not be detected by a pneumococcal bactericidal assay.

The importance of splenic blood flow in clearing pneumococcal organisms

Overwhelming infection from encapsulated bacteria occurs after splenectomy. Decreases in IgM, tufsin, and serum opsonin are known to occur in animals and humans after splenectomy. A substantial immunologic advantage exists if some splenic tissue remains, but this may not offer sufficient protection from encapsulated bacteria if splenic arterial blood flow is reduced. This experiment was designed to examine the rate of pneumococcal clearance by the spleen and to determine the relationship between splenic blood flow and splenic tissue mass in bacterial clearance from the blood. Pneumococcal clearance, splenic blood flow, and residual splenic weight were measured in 171 rabbits with normal spleens, ligated splenic arteries, splenic autotransplants, hemisplenectomies, and splenectomies. Interruption of the splenic artery results in delayed pneumococcal clearance that is due to reduced blood flow and not to a decrease in splenic tissue mass. Splenic artery ligation to preserve an injured spleen cannot be assumed to give protection from sepsis.

Pneumococcal bacteraemia--a study of 75 black children

Seventy-five black children from 0 to ten years old with pneumococcal bacteraemia, who were hospitalized during a one-year period, were studied retrospectively from case records. Half the children were under one year and 68% under two years of age. Sixty-seven per cent were malnourished, 34% severely so. The overall case-fatality-rate was 26.7% being highest in children presenting in autumn (52.4%) and in those with meningitis (54.5%), severe protein-calorie malnutrition (42.8%) or associated infections (61.5%). Host defences against the pneumococcus are discussed, especially in relation to their deficiencies in malnourished and young children. Special mention is made of early-onset neonatal sepsis due to the pneumococcus and of the association between pneumococcal bacteraemia and acute post-streptococcal glomerulonephritis. This study indicates that pneumococcal bacteraemia is a serious infection in children, especially in those with malnutrition and other infections. In view of the emergence of penicillin-resistant strains, its treatment may become more difficult in the future.

The effect of partial splenectomy on experimental pneumococcal bacteremia in an animal model

The effect of total and partial splenectomy on the blood stream clearance of type 23B Streptococcus pneumoniae was studied in chinchillas 2 wk and 2 mo following surgery to determine the amount of splenic tissue necessary for protection against overwhelming sepsis. Significantly more pneumococci were found in the blood of totally splenectomized chinchillas than in the blood of sham-operated animals throughout the 6-hr sampling period after intravenous inoculation of pneumococci. Animals that had two-thirds of their spleen removed demonstrated a significant delay in clearance of pneumococci compared with sham-operated and hemisplenectomized animals. The rate of pneumococcal clearance was similar for the sham-operated and the hemisplenectomized group, and was significantly prolonged but similar among totally splenectomized and two-thirds splenectomized animals. Pneumococcal opsonic activity was reduced only in the sera of totally splenectomized chinchillas 2 mo after surgery. There was no positive relationship between pneumococcal clearance and change in pneumococcal opsonic activity. These results suggest that the impaired clearance of circulating pneumococci in splenectomized animals is due to the loss of splenic reticuloendothelial cells as a mechanical filter, rather than deficient serum opsonic activity. There appears to be a critical splenic mass required for optimal bacterial clearance, and hemisplenectomy may protect against overwhelming postsplenectomy sepsis.

Opsonic requirements for intravascular clearance after splenectomy

We investigated the opsonic requirements for intravascular clearance of pneumococci in guinea pigs and of sensitized erythrocytes in human beings after splenectomy. The impaired clearance of injected pneumococci in splenectomized guinea pigs was corrected by immunization. This improvement in clearance was due to increased hepatic sequestration of organisms. There was a significant delay in antibody-mediated clearance of autologous erythrocytes sensitized with IgG (P < 0.001), although the rate of complement-mediated clearance in splenectomized patients was normal. A fourfold increase in sensitizing antibody resulted in a significant improvement in clearance that was due to increased hepatic sequestration (P < 0.005). One patient who had an intact spleen and who had previously received Thorotrast (thorium oxide) had impaired antibody-mediated clearance despite increased sensitization. These observations suggest that, after splenectomy the remaining macrophages of the reticuloendothelial system require increased amounts of antibody to mediate efficient intravascular clearance of opsonized particles.

Immunologic consequences of neonatal splenectomy

The hazard of overwhelming postsplenectomy infection has been suggested to be greatest in children operated upon before 1 yr of age. In this work immune functions of 3 children, splenectomized within 2 days after birth were studied. The opsonic activity of the sera of all patients towards pneumococcus was decreased. The other immunologic findings were normal. These observations support the concept that all splenectomized patients should receive pneumococcal polysaccharide vaccine and in case of any infection adequate antibiotic therapy must be started very soon after the first symptoms.

Activity of the alternative complement pathway after splenectomy: comparison to activity in sickle cell disease and hypogammaglobulinemia

Patients with sickle cell disease and individuals who have undergone splenectomy share defects of certain host defense mechanisms and a predisposition to severe pyogenic bacterial infections. Since patients with sickle cell disease can have deficient activity of the alternative complement pathway, we have tested such activity in sera from splenectomized children and adults. A new kinetic hemolytic assay has been used, and we have compared results to those obtained with sera from patients with sickle cell disease or hypogammaglobulinemia. Sera from six of 58 splenectomized individuals (10%) had defective function of the alternative pathway, compared to 10 of 62 sera from patients with sickle cell disease (16%) and 10 of 18 sera from hypogammaglobulinemic patients (56%). Deficiency of antibody, a rate-influencing component of alternative pathway activity in this system, appears responsible for deficient activity in the hypogammaglobulinemic sera. The molecular basis for the deficiency found in sickle cell disease or after splenectomy is not clear. Defective function of the alternative complement pathway could contribute to the increased predisposition to bacterial infection that exists in these three patient groups.

Splenic function: normal, too much and too little

This review is concerned with normal splenic function, mechanisms and consequences of splenomegaly, hypersplenism, the medical indications for splenectomy and the various aspects of hyposplenism. The potential probelm of lethal septicemia in hyposplenic or asplenic patients is also considered.

Sepsis and congenital asplenia

Fifty-nine children with congenital asplenia were reviewed for episodes of severe infection. Seven children had isolated asplenia and 52 had asplenia associated with complex congenital heart disease (asplenia syndrome). A control group of eusplenic children with comparable cardiac lesions were assembled and used for comparative statistical analysis. There were 16 instances of documented sepsis among 59 children (27%). In those less than six months of age, the invading organism was usually gram-negative (Escherichia coli or Klebsiella). In children six months of age or older, the infecting organism was usually a pneumococcus or H. influenzae. When those with asplenia syndrome were compared to the control population, the former group had a significantly greater incidence of sepsis. Children with asplenia syndrome who survived the first month of life were at greater risk of dying from sepsis than from their heart disease. It is recommended that prophylactic antibiotics be administered to children with congenital absence of the spleen, commencing at three months of age, to be continued indefinitely.

The morbidity and mortality of splenectomy in childhood

One hundred and eighty-two patients undergoing splenectomy in infancy and childhood were followed for periods of 2 to 15 years. Serious infections occurred in 11 patients (6%) with death in 6 (3.3%). In 10 patients the infection was sepsis, and in all but one patient the infection occurred within 2 years of splenectomy. Among children over 2 years of age the risk of infection was still appreciable except when the spleen was removed incidentally or for traumatic rupture. Splenectomy for thalassemia and portal hypertension resulted in an increased risk of serious infections when compared with removal of the spleen for hereditary spherocytosis, idiopathic thrombocytopenic purpura, trauma, or for technical reasons in the course of another operation. Post-splenectomy infections tended to follow a characteristic pattern. The infecting organism was predominantly pneumococcus, the course was fulminating and the mortality high.

Overwhelming postsplenectomy infection

One of the more intriguing aspects of the spleen is the protection against certain bacterial infections afforded by its unique vascular and immune function. There have been extensive clinical surveys which indicate an incidence of overwhelming postsplenectomy infection (OPSI) above that of the disease for which the splenectomy was done. In the absence of the spleen, either congenital or subsequent to surgical removal, this overwhelming sepsis has a 50% case fatality rate. The most common infective organism has been Diplococcus (tstreptococcus) pneumoniae (D. pneumoniae). Intensive investigations indicated loss of phagocytic function of the spleen, depression of serum IgM levels, a possible suppression of the lymphocyte responsiveness, and changes in opsonin-alternative complement system as potential causes of OPSI. Preventive measures against OPSI include trials of prophylactic Phenoxymethyl Penicillin (penicillin) and pneumococcal vaccine.

Splenectomy in childhood: a review in England and Wales, 1960-4

An investigation was carried out of 821 children under the age of 16 years who were subjected to splenectomy in England and Wales during the 5 years 1960-4. A postal follow-up study provided satisfactory information concerning 96 per cent of these. Excluding early postoperative deaths, practically all the cases were followed up for 2 years or more and 70 per cent for more than 5 years. Forty-nine children had died since operation, 32 from underlying disease and 17 from infection. Fifty children (6 per cent of the survivors) had major infections considered to be due to the primary condition aggravated by splenectomy. Seven died, all from the primary disease. Sixteen children (2 per cent) developed septicaemic illnesses and 10 died. In these the effect of splenectomy was considered to be the primary factor. Fourteen of the 16 had been operated on in the first 4 years of life. Practically all the serious infections occurred within 3 years of operation and pneumococcus was the organism most frequently implicated. Ninety per cent of the splenectomies in childhood were performed for accidental injury, congenital haemolytic anaemia or idiopathic thrombocytopenic purpura. Accidental injury to the spleen rarely occurs in very young children, and in the other two conditions splenectomy can usually be safely delayed untile over the age of 3 years. If this is achieved it is estimated that the unavoidable risk of dangerous infection is less than 1 per cent. One in 10 splenectomies will be carried out for severe and potentially fatal illnesses and in this situation the risk from operation is of secondary importance. Many such conditions carry increased susceptibility to infection per se or because corticosteroids or other immune suppressants are used in their management. It is recommended that splenectomy be avoided if at all possible during the early years of life. It is further recommended that prophylactic penicillin be administered for 3 years following operation whatever its indication and whatever the age of the patient. If the underlying condition itself carries risk of infection more active and more prolonged prophylaxis may be indicated.