Active Immunization as a Means of Prevention of Hospital Pneumonia

S.V. Tsarenko, V.B. Khvatov, N.A. Mikhalova, V.V. Krylov, S.S. Petrikov, V.Yu. Zinkin, E.V. Gukova, Yu.V. Titova, Kh.T. Guseinova

Sklifosovsky Research Institute of Emergency Care,
Mechnikov Research Institute of Vaccines and Sera, Moscow, Russia

 

Pyoseptic complications are one of the main problems of intensive care in patients with intracranial hemorrhages, being in a critical state. A resuscitation department of a hospital of emergency care is characterized by circulation of formed polyresistant strains of pathogenic microorganisms. Pneumonia is caused by microbes in the majority of cases. Antibacterial therapy is not always effective. Thus, one of the ways, which can effect the existent situation, is active immunization with polyvalent vaccines.

The goal of the present study was to investigate an effect of immunization with a Staphylococcus-Proteus-Pseudomonas aeruginosa adsorbed (SPPA) vaccine on a rate and term of pneumonia development in patients with craniocerebral hemorrhages, being in a critical state.

Materials and Methods. There were 145 patients with craniocerebral trauma, ruptures of aneurysms of cerebral arteries and hemorrhagic strokes. A criterion of including a patient into groups under study was absence of stomach contents aspiration at the previous stages of treatment and pyoseptic complications on admission to the neuroresuscitation department.

There were two groups of patients. Single inoculation with the SPPA vaccine (produced by IMMUNOPREPARAT, located in Ufa, Tatarstan) was used in cases of the first group (n=19). It was administered subcutaneously in a dose of 0.5 ml during the first day of staying in the neuroresuscitation department. Patients of the control group (n=126) were not subject to active immunization. The groups were comparable in age, sex, a disease character, a state severity, a period of stay in the resuscitation department, duration of artificial respiration and methods of intensive care. A degree of consciousness depression was characterized by a score of 9 (Glasgow Coma Scale) in 73% and 69% of cases of the main and control groups respectively. Monitoring of a term and rate of pneumonia development was carried out. Immune status dynamics was estimated on the 1-3, 4-13 and 14-30 day of hospitalization. Absolute and relative numbers of leukocytes, a granulopectic index (a latex test), activity of oxygen-dependent metabolism of neutrophils (a photometric test with tetrazolium) and serous concentrations of IgM, IgG and IgA were estimated.

Results. Pneumonia developed in 36.8% of cases of the main group. It was watched in 46.1% of patients of the control group (p=0.61). There was a reliable difference in a term of appearance of inflammatory changes in the lungs. The patients of the main and control groups developed pneumonia on the 9.3±4.2 day (M±d) and 6.0±2.2 day after admission to the resuscitation department respectively (p<0.0001).

Increase of IgA, IgM and IgG titers in patients of the main group was watched beginning with the 4th day after vaccination. IgA titer was practically similar in both groups by the third week of hospitalization, despite the fact, that initial concentration of IgA in the group of inoculated patients was lower than normal values and reliably smaller than identical indices in the control group (1.6±1 g/l versus 2.2±1 g/l; p=0.034). Concentration of IgA, playing the most important part in local immunity of mucous membranes, and its dynamics were regarded to be an inoculation effect. It was confirmed by clinical results. IgM titers increased in both groups. However, concentration of IgM (a marker of an acute humoral response to infection) in the main group was reliably higher than in the control group during the second week (2.1±0.8 g/l versus 1.4±0.6 g/l) of hospitalization. One could observe a growing level of IgG in both groups. It reached its peak values by the 14-30 day. IgG concentraton increased by 56% and 33% in the main and control groups respectively (12.3 g/l a nd 10.7 g/l; p<0.05).

It is important to note, that vaccination did not result in any considerable changes of cellular or phagocytic links of immunity.

Conclusions

  1. Active immunization with the SPPA vaccine, carried out as a constituent part of standard measures of hospital pneumonia prevention in cases with intracranial hemorrhages, allows to reduce its rate and to achieve a reliable delay of its arising.
  2. Immunization with the SPPA vaccine leads to growth of IgM concentration and normalization of IgA level, beginning with the second week of hospitalization.