Pneumococcal vaccine improves pulmonary clearance of live pneumococci after splenectomy

The efficacy of pneumococcal capsular polysaccharide vaccines after splenectomy to decrease the incidence of postsplenectomy pneumococcal sepsis is controversial. We examined the effect of pneumococcal vaccine on clearance of live pneumococci from lungs of splenectomized and sham-operated mice following an aerosol challenge of pneumococci. Splenectomy impaired clearance of pneumococci from mouse lungs and allowed for increased translocation of pneumococci to tracheobronchial lymph nodes compared to shams (P less than 0.01). Pneumococcal vaccine improved lung clearance in both splenectomized and sham-operated mice compared to saline controls (P less than 0.01), but the number of live pneumococci recovered from lung pairs was greater in splenectomized mice compared to shams (P less than 0.01). Pneumococcal vaccination facilitated earlier translocation of pneumococci to tracheobronchial lymph nodes, and probably promoted bactericidal activity in these nodes, in both splenectomized and sham-operated mice. Survival in splenectomized mice was improved by vaccination, but remained significantly less than that in saline-treated sham-operated mice (P less than 0.0009). The data show that pneumococcal vaccine can improve lung antipneumococcal defenses in splenectomized mice, but not to the same degree as in mice retaining their spleens. Pneumococcal vaccine should be given after splenectomy, but surgeons should caution patients that it may be less effective than when given to individuals with intact spleens or before elective surgery.     

Pneumococcal vaccine in children and young adults with chronic renal disease

BACKGROUND.: Pneumococcal vaccination has been recommended for immunocompromisedchildren over 2 years including patients with chronic renaldisease. However, the effect of vaccination and revaccinationis variable and the indication for immunization is a subjectof controversy. METHODS.: Forty children and young adults with chronic renal diseases(including the idiopathic nephrotic syndrome, chronic renalfailure, patients undergoing dialysis and after transplantation)were vaccinated with a 23-valent pneumococcal vaccine. The efficacyof the vaccine was evaluated by measuring antibody titres beforeand 4 weeks, 6 months, and 12 months after vaccination. Twenty-twopatients were submitted to a revaccination 1 year after thefirst vaccination. RESULTS.: A sufficient immune response, defined as an at least fourfoldincrease of postvaccinal antibody titres and an antibody titre>200, was observed in 83% of the patients 4 weeks after vaccination,but only in 68% after 6 months, and in 48% after 1 year. Revaccinationproduced a significant immune response in 11/22 patients (50%)followed by a rapid decline of antibody levels within 6 months.Both vaccinations were well tolerated. CONCLUSIONS.: The currently available vaccine is without major side-effectsand effective in producing a significant immune response. Antibodylevels should be monitored in vaccinated patients with chronicrenal diseases considering the rapid decline as early as 6 monthsafter vaccination. Evaluation of the efficacy of revaccinationin these patients requires further investigations.     

Pneumococcal polysaccharide vaccine responses are impaired in a subgroup of children with cystic fibrosis

BackgroundPneumococcal immunization is recommended in children with cystic fibrosis (CF). To date, however, there are no published studies on the efficacy of pneumococcal vaccination in this group of patients.MethodsWe carried out a retrospective study of serotype-specific pneumococcal antibody responses to immunization with Prevenar 7 and Pneumovax II in a cohort of children with CF.ResultsNine children had been immunized with Prevenar 7, and all had serotype-specific pneumococcal antibody levels in the protective range (> 0.35 mg/L) to all 7 immunizing serotypes. In contrast, only 7 of 33 patients (21%) immunized with Pneumovax II made protective antibody responses to all 7 serotypes, and 3 failed to make protective antibodies to any of the serotypes. Controlling for age as a confounder in the analysis, children with impaired antibody responses to pneumococcal polysaccharide (Pneumovax II) immunization had lower Shwachman–Kulczycki scores than children with normal polysaccharide antibody responses. All isolates of Pseudomonas aeruginosa occurred in patients with impaired anti-pneumococcal antibody responses, and a broader range of respiratory pathogens was isolated from these children.ConclusionsImpaired antibody responses to immunization with Pneumovax II are common in children with CF and this may be associated with increased disease severity.     

Pneumococcal nephritis

Four cases are presented in which azotemia developed associated with pneumococcal pneumonia. The pathologic problem is thought to be secondary to disseminated intravascular coagulation with the development of hyaline and fibrin thrombi in the glomeruli. Rats were infected with pneumococcos Type 1; 20 per cent became azotemic and glomerular lesions developed. The literature on pneumococcal nephritis and the association of pneumococcal sepsis and an absent spleen with disseminated intravascular coagulation are discussed.     

Pneumococcal aortic valve endocarditis causing aortopulmonary artery fistula.

We report a case of an aortic-pulmonary artery fistula secondary to acute bacterial endocarditis and aortic root abscess formation. The patient presented with generalized symptoms and an initial pneumococcal pneumonia, then developed respiratory and cardiac failure necessitating ventilation and inotropic agents. An echocardiogram showed a vegetation in the aortic valve, an abscess involving the aortic root, and suggested a fistula between the aorta and main pulmonary artery, which was confirmed at emergent operation. Despite a complicated early postoperative course the patient has made a full recovery.     

Pneumococcal septicaemia with Purpura fulminans in an 11-month-old child.

Purpura fulminans (PF) is a syndrome characterised by acute onset of rapidly progressive haemorrhagic necrosis of the skin due to dermal vascular thrombosis, mainly occurring during meningococcal sepsis. It occurs rarely in the course of infection with Streptococcus pneumoniae and most cases report Meningococcus as the causing agent. This is a case report of successful conservative limb-preserving management of PF and sepsis caused by Streptococcus pneumoniae in an 11-month-old girl.     

Pneumococcal conjugate vaccine--a health priority

Pneumonia is a major cause of childhood mortality and morbidity. Streptococcus pneumoniae is the most important bacterial pathogen causing pneumonia in children. The HIV epidemic has increased the burden and severity of childhood pneumococcal pneumonia and invasive disease fortyfold. Pneumococcal conjugate vaccine (PCV) is a highly effective intervention to reduce invasive pneumococcal disease and pneumonia. Studies evaluating a 9-valent PCV in South Africa and The Gambia reported a 72 - 77% reduction in vaccine-serotype-specific invasive disease in vaccinated children. As many of the pneumococcal serotypes associated with antibiotic resistance are included in PCV, vaccination has also been associated with a reduction in antimicrobial-resistant invasive disease. PCV may also reduce childhood mortality, especially in places with limited access to health care, as shown in Gambian study in which PCV reduced childhood mortality by 16%. In addition to the direct effects of PCV, there is a substantial reduction in disease burden through indirect protection of non-vaccinated populations. PCV is immunogenic in HIV-infected children and provides protection against invasive disease or pneumonia in a substantial number of children. Although the efficacy of PCV for prevention of invasive disease or pneumonia is lower in HIV-infected compared to -uninfected children, the overall burden of disease prevented is much greater in HIV-infected children because of the higher burden of pneumococcal disease in these children. Consequently, vaccine-preventable invasive disease is almost 60 times higher in HIV-infected compared to -uninfected children, while the reduction in pneumonia in HIV-infected children is 15 times greater. However, the long-term efficacy of PCV wanes in HIV-infected children who are not taking antiretroviral therapy, and booster doses are probably indicated. Although there is concern about the potential for replacement disease due to non-vaccine serotypes, a substantial and sustained reduction in invasive disease has occurred overall in populations with widespread childhood immunisation. Routine childhood immunisation is now the standard of care in most developed countries. However, PCV is much less accessible to children in developing countries due to cost and availability. Cost-effectiveness analysis indicates that use of PCV is potentially highly cost-effective, at tiered pricing, even in very low-income countries. Widespread availability and vaccination with PCV is urgently needed for all children under 2 years of age in South Africa. In addition, the use of PCV for all HIV-infected children under 9 years should be prioritised.     

Pneumococcal vertebral osteomyelitis: a unique case with atypical clinical course.

STUDY DESIGN: A case report. OBJECTIVES: To report and discuss a case of pneumococcal vertebral osteomyelitis with meningitis in a previously healthy 51-year-old immunocompetent woman who presented with acute onset lower back pain. SUMMARY OF BACKGROUND DATA: To the authors' knowledge, pneumococcal vertebral osteomyelitis with meningitis in an immunocompetent person with no other predisposing factor has not been reported previously. METHODS: The patient was diagnosed to have pneumococcal meningitis 10 days after the onset of acute and severe lower back pain. Significant improvement of clinical symptoms from meningitis was achieved with appropriate antimicrobial treatment. Lumbar CT and MRI scans were performed on persistence of fever and lower back pain. Loss of height and peridiscal inflammation at L3-L4 and epidural and bilateral psoas abscesses were detected. RESULTS: Diagnosis of pneumococcal vertebral osteomyelitis was established after evaluation of the material obtained from CT-guided aspiration of the psoas abscess and biopsy of the L3 body. With appropriate antimicrobial treatment, the patient's complaints resolved completely. CONCLUSION: To the authors' knowledge, this is the first reported case of pneumococcal vertebral osteomyelitis with meningitis.     

Pneumococcal antigen detection in bronchoalveolar lavage fluid from patients with pneumonia.

BACKGROUND--Pneumococcal pneumonia can be diagnosed by the detection of capsular antigen in sputum, serum, pleural fluid, or urine using countercurrent immunoelectrophoresis and latex agglutination. In addition, quantitative cultures of bronchoalveolar lavage (BAL) fluid are also reliable for establishing the aetiology of pneumonia. This study investigated the value of rapid detection of pneumococcal antigen in BAL fluid from patients with pneumonia. METHODS--Pneumococcal antigen was detected by countercurrent immunoelectrophoresis and latex agglutination. Patients were grouped according to BAL quantitative culture results into pneumococcal pneumonia (n = 24), other known aetiology (n = 18), and unknown aetiology (n = 17). Thirteen patients with interstitial lung disease and without pneumonia served as a control group. RESULTS--In patients with pneumococcal pneumonia, antigen was detected by countercurrent immunoelectrophoresis in 50% and by latex agglutination in 54% of cases. In patients with pneumonia of unknown aetiology pneumococcal antigen was detected by latex agglutination in 53% of cases. Antigen was not detected in patients with pneumonia of other known aetiology or in control patients, yielding a specificity of 100%. CONCLUSIONS--In patients with pneumococcal pneumonia requiring fibreoptic bronchoscopy detection of pneumococcal antigen in BAL fluid may rapidly and accurately confirm the aetiology. Furthermore, in nearly half the cases of pneumonia of unknown aetiology antigen can be detected, suggesting that Streptococcus pneumoniae is a major causative agent in such patients.     

Pneumococcal serotypes in sputum isolates during acute respiratory illness in Edinburgh.

During the years 1978-83 serotyping was carried out on all sputum isolates of pneumococci obtained from patients in the chest wards of the City Hospital, Edinburgh. In 402 patients with acute respiratory illness the peak isolation rates occurred from January to April, and the serotype distribution was similar to that seen in previous UK studies, the commonest types being 3, 6, 9, 19, 23, and 8. The overall mortality rate was 8.7%, the serotype distribution in fatal cases reflecting the distribution of the whole group. The presence of mixed infection, predominantly with Haemophilus influenzae, was associated with a lower mortality rate of 3.5%. Nearly all patients (92%) were either elderly or had a chronic underlying disease and only one death occurred in a patient under 70 years who had no pre-existing disease. Of the pneumococcal serotypes isolated from the 292 patients with chronic chest disease, 82% are included in the new 23 valent pneumococcal vaccine and the efficacy of this needs to be assessed further in high risk patients.