The relationship between Severity of the Systemic Inflammatory Response Syndrome (SIRS) and Its Etiology and Outcome

Document Type : Research Paper



ntroduction: SIRS is known as a condition with the presence of four criteria of: Fever or hypothermia. Tachypnea. Tachycardia. Leukocytosis or leukopenia or bandemia. Sepsis is defined as the SIRS with an infectious etiology. Incidence rate is increasing during the recent 15 years. The key point in treatment of sepsis is early diagnosis and beginning of treatment according to the signs before the occurrence of complications like hypotension. This study was done to evaluate the relationship between the severity of SIRS and its etiology and outcome.
Materails and Methods: This descriptive study was carried out in the year 2004 on 306 cases of SIRS, referring to Infectious ward of Imam Reza hospital, Mashhad, Iran. The study was accomplished through completing questionnaires, after getting medical history, physical and laboratory examinations (including CBC, urine analysis, platelet count, and ESR) of patients. Then the sensitivity, specififity and positive predictive values for SIRS regarding differentiation of infectious from non- infectious diseases were studied. In addition, the severity of SIRS and its effects on mortality, also, the effects of severe SIRS on any infection in platelet count and ESR were evaluated. The Results were arranged as charts, graphs and described by MANN-WHITENY, T-student.
Results:According to the number of patients final diagnosis included pneumonia (n=56), meningitis (n=35), unknown origin infections (n=34), urosepsis (n=25), and miscellaneous etiologies such as brucellosis, hepatitis, etc. There were 23 non-infectious patients and 17 mortal cases. The highest mortality rate was in pneumonia (n=7) that often had serious leukocytosis. Severe SIRS has 20.1 % sensitivity and 95 % positive predictive value for diagnosis of infection.
Conclusion: There was no statistically significant difference between the two groups, regarding the primary vital signs, laboratory findings, age, sex, and mortality rate. The mortality rate didn't have any relationship with thrombocytopenia, increased ESR or sex; but was related to hypotension, serious leukocytosis and severity of SIRS. Based on the primary vital signs and laboratory findings, the severity of SIRS has a clear correlation with the mortality rate. Heuce it is recommended that much attention should be paid to the documents of vital signs and routine laboratory findings for the early diagnosis and treatment.


1- American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference Committee.
Definitions for sepsis and organ failure and guidelines for the use of innovative therapies in sepsis. Crit Care Med
1992; 20:864–874.
2- Watson RS, Carcillo JA, Linde-Zwirble WT, et al. The epidemiology of severe sepsis in children in the United
States. Am J Respir Crit Care Med 2003;167:695–701.
3- Alberti C, Brun-Buisson C, Goodman SV, et al. Influence of systemic inflammatory response syndrome and
sepsis on outcome of critically ill infected patients. Am J Respir Crit Care Med 2003; 168:77–84.
4- Mandell, Douglas, Bennets. Principles and practice of Infectious Disease. 6th ed. Philadelphia: Churchill
Livingstone; 2005.
5- Mitaka C. Clinical laboratory differentiation of infectious versus non-infectious systemic inflammatory response
syndrome. Clin Chim Acta 2005; 351(1-2): 17-29.
6- Shibata K, Funada H. The epidemiology of SIRS.Sepsis in JapanNippon Rinsho 2004; 62(12):2184-8.
7- Sun D, Aikawa N. The natural history of the systemic inflammatory response syndrome and the evaluation of
SIRS criteria as a predictor of severity in patients hospitalized through emergency servicesKeio. J Med 1999;
8- Shapiro NI, Howell M, Talmor D. A blueprint for a sepsis protocol. Acad Emerg Med 2005 Apr; 12(4): 352-9.