Relevance of Blood Culture to the Diagnosis and Treatment of Septicemia
Chapter One
OBJECTIVES OF THE RESEARCH
This objectives of this research are to;
Determine the relevance of blood culture to the diagnosis and treatment of septicaemia.
Compare the occurrence of Gram positive and Gram negative bacteria in the subjects with culture – proven septicaemia.
Determine which gender(male or female) is more prone to septicaemia.
CHAPTER TWO
LITERATURE REVIEW
What is septicemia?
Septicemia is a serious bloodstream infection. It’s also known as blood poisoning.
Septicemia occurs when a bacterial infection elsewhere in the body, such as the lungs or skin, enters the bloodstream. This is dangerous because the bacteria and their toxins can be carried through the bloodstream to your entire body.
Septicemia can quickly become life-threatening. It must be treated in a hospital. If left untreated, septicemia can progress to sepsis.
Septicemia and sepsis aren’t the same. Sepsis is a serious complication of septicemia. Sepsis causes inflammation throughout the body. This inflammation can cause blood clots and block oxygen from reaching vital organs, resulting in organ failure.
The National Institutes of Health estimates that over 1 million Americans get severe sepsis each year. Between 28 and 50 percent of these patients may die from the condition.
When the inflammation occurs with extremely low blood pressure, it’s called septic shock. Septic shock is fatal in many cases.
What causes septicemia?
Septicemia is caused by an infection in another part of your body. This infection is typically severe. Many types of bacteria can lead to septicemia. The exact source of the infection often can’t be determined. The most common infections that lead to septicemia are:
urinary tract infections
lung infections, such as pneumonia
kidney infections
infections in the abdominal area
Bacteria from these infections enter the bloodstream and multiply rapidly, causing immediate symptoms.
People already in the hospital for something else, such as a surgery, are at a higher risk of developing septicemia. Secondary infections can occur while in the hospital. These infections are often more dangerous because the bacteria may already be resistant to antibiotics. You’re also at a higher risk of developing septicemia if you:
have severe wounds or burns
are very young or very old have a compromised immune system, which can occur from conditions, such as HIV or leukemia, or from medical treatments such as chemotherapy or steroid injections have a urinary or intravenous catheter are on mechanical ventilation
What are the symptoms of septicemia?
The symptoms of septicemia usually start very quickly. Even in the first stages, a person can look very sick. They may follow an injury, surgery, or another localized infection, such as pneumonia. The most common initial symptoms are:
chills
fever
breathing very fast
rapid heart rate
More severe symptoms will begin to emerge as septicemia progresses without proper treatment. These include the following:
confusion or inability to think clearly
nausea and vomiting
red dots that appear on the skin
reduced urine volume
inadequate blood flow
shock
It’s crucial to get to the hospital right away if you or someone else is showing signs of septicemia. You shouldn’t wait or try to treat the problem at home.
CHAPTER THREE
MATERIALS AND METHODS
Introduction
In this chapter, we would describe how the study was carried out.
Research design
Research design is a detailed outline of how an investigation took place. It entails how data is collected, the data collection tools used and the mode of analyzing data collected (Cooper & Schindler (2006). This study used a descriptive research design. Gill and Johnson (2002) state that a descriptive design looks at particular characteristics of a specific population of subjects, at a particular point in time or at different times for comparative purposes. The choice of a survey design for this study was deemed appropriate as Mugenda and Mugenda (2003) attest that it enables the researcher to determine the nature of prevailing conditions without manipulating the subjects.
Further, the survey method was useful in describing the characteristics of a large population and no other method of observation can provide this general capability. On the other hand, since the time duration to complete the research project was limited, the survey method was a cost effective way to gather information from a large group of people within a short time. The survey design made feasible very large samples and thus making the results statistically significant even when analyzing multiple variables. It allowed for many questions to be asked about a given topic giving considerable flexibility to the analysis. Usually, high reliability is easy to obtain by presenting all subjects with a standardized stimulus; observer subjectivity is greatly eliminated. Cooper and Schindler (2006) assert that the results of a survey can be easily generalized to the entire population.
Study Population
The subjects comprised six hundred and fifty (650) children and adults of both sexes aged between one day to 70 years having clinical features suggestive of septicaemia, who were on admission at University Of Nigeria Teaching Hospitals (UNTH), Enugu. Some of the clinical diagnosis was lung absess, puerperal sepsis, septic abortion, meningitis, birth asphyxia, burkitt lymphoma, postoperation fever, encephalitis etc. All patients that were already on antibiotic therapy were excluded.
CHAPTER FOUR
RESULTS
A total of 650 patients who fulfilled the criteria for diagnosis of presumed septicaemia were bacteriologically screened. These included 33 (5.0%)
neonates, 109 (16.8%) children and 508 (78.25%) adults. An etiology could be established in 204 subjects indicating incidence of 31.4%. In total, blood samples of 420 (64.6%) patients were bacteriologically sterile and 26 (4%) of their blood samples grew contaminants. No growth in the negative (sterility) controls of the two blood culture broths while there was a profuse growth in the positive controls.
CHAPTER FIVE
DISCUSSION OF FINDING, CONCLUSION
DISCUSSION
The findings of this study revealed that Septicemia still remains the major killer disease in Nigeria (Eugene, 1998). Although its incidence of 31.4% found in this study is higher than the 26% reported by Akuse et al. in 1984 at Ibadan among the neonates, it fell within the range of 15- 35% reported by Shanson in 1999. This study has established that the disease affects all age groups but it was noticeable that neonates, children and teenagers were more vulnerable than adults as persons between years of 0-20 years were most infected. This vulnerability was most prominent, pronounced and apparent among the neonates because they accounted for the majority (16.2%) of the patients that had culture–proven septiceamia in this study. It was observed that septicaemia was most prevalent in the first week of life and reduced remarkably with age increase (Table 1). This difference in age distribution of the infection was statistically significant (P< O). The higher occurrence in childhood septicaemia has been reported from different parts of Nigeria (Akuse et al., 1998; Akpede et al., 1996, Ako-Nai et al., 1999, Angyo et al., 2001; Owa et al., 1988; Olusanya et al., 1991). The high occurrence of neonatal septiceamia in Ile-Ife may probably be adduced to their low immune response, socio-economic status of the parents, poor hygiene practices, bottle feeding and high incidence of delivery at home. An additional effect of their low socio-economic status is exhibited by the inability of their parents to pay the hospital fees charged for delivery; consequently they deliver at home, churches, maternity centre or herbalist shrines where there are no proper midwifery facilities. Infections of neonates may be due to contamination as a result of poor hospital hygiene and inadequate hand – washing by staff, impairment of host principal effect of low socio-economic status is the inability of the indigent mothers to maintain successful lactation as it is necessary for the mother to be mentally and physically healthy (Beischer et al., 1979).
There was no statistically significant difference in gender variation in septicaemia, it is interesting to notice that males has a higher prevalence level than the females, though this slight variation has been previously documented by various authors (Bnetow, 1965; Behrman 1977). This higher prevalence in male may be adduced to exposure factors and peculiar behavioural attitudes/activities of them which make them more prone to accidents. This reason cannot be advanced to higher occurrence of neonatal septiceamia in males than females. Although no author has proffered any reason for this, it may be ascribed to genetic basis.
It is noteworthy that Gram positive organisms were more predominant than Gram negative ones. This is contrary to the earlier reports by Owa et al. (1988) at Wesley Guild Hospital, Ilesa, Alausa et al. 1984 at Ibadan and Dawodu et al. (1980) but conforms with those of Antia–Obong et al. (1990), Njokanma et al. (1990), Olusanya et al (1991) Ako-Nai et al. (1999) and Angyo et al. (2001). Of the Gram–positive bacteria, the three common microbes were S. aureus, S. albus and Streptococcus faecalis among which Staphylococcus aureus had the highest occurrence while Klebsiella sp. was the most predominant among the Gram negative bacteria, followed by E. coli and Pseudomonas sp. However, the four most common microbes isolated from blood cultures in this study were S. aureus, Klebsiella sp., coli and S. albus respectively in descending order. S. aureus was still the leading cause of Septicemia. This observation is in agreement with the work of some authors (Owa et al., 1988; Alausa et al., 1984; Olusanya et al., 1991; Ayliffe et al., 1977; Ako–Nai et al., 1999) but deviates from the reports from some hospitals from undeveloped countries by some authors. Gorbach and his colleagues (1992) reported that E. coli was the preponderant microbe. The occurrence of Klebsiella sp. in this study is in tandem with the findings of Olusanya et al. (1991), Ako-Nail et al. (1999) and Angyo et al. (2001) in Nigeria but at a wide variance with that of Ghanshyam et al (2002) in India. This work further revealed that there is drastic reduction in the incidence of septicaemia due to anaerobes in this 20th century which is contrary to the report of several authors (Stoke, 1958) about four decades 19th century. This observation was in similitudes of discovery of Mandell and colleagues (1995). The decline of detectable anaerobic septicaemia in many hospitals may be advanced to the wide spread use of antibiotics active against them especially in surgical prophylaxis. The significance of anaerobes in septicaemia has been explicitly demonstrated by Chow et al. (1994). The preponderance of facultative anaerobes in the blood cultures in this work which is completely in conformity with earlier reports of other authors (Shanson et al., 1999; Eugene et al., 1998) may be related to their defences and instrumentation and surgery. The other ability to live and survive in both anaerobic and anaerobic environment.
It has also been demonstrated in this study that most of the septicaemic episodes were caused by a single organism (Monomicrobe) while polymicrobial aetiology was observed in only a few cases. This observation is in consonance with earlier reports (Bartlett et al., 1974; Ghanshyam et al., 2002; Angyo et al., 2001). In Indian reports, polymicrobial aetiology was documented in 8% of cases by Thomas et al. (1999) and 6.8% in another study by Ghanshyam et al. (2001) which are very similar to the incidence of 7.8% in this study. A western study reported an incidence of 3.9% of polymicrobial sepsis. Comparatively, this indicates that incidence of polymicrobial sepsis in developing countries is higher than in developed countries of the world. The decrease in incidence of septicaemia in developed countries may be due to proper sanitation which has successfully diminished the infection in more affluent regions of the world. Most clinical bacteriologists failed to report polymicrobial sepsis because of misconception of contamination, ignorance of its significance or disregard for the second organism in an already positive culture (Sharma et al., 1987; Mathur et al., 1994; Mondal et al., 1991). However, there is a need to correlate the occurrence of polymicrobial sepsis with clinical outcome in septicaemia. A patient already infected with one microbe may have acquired the second one from the hospital environment or both the bacteria could be nosocomial in origin.
A study of in vitro antimicrobial susceptibility profile of the aetiological agents of septicaemia has revealed that there is a growing emergence of multi-drug resistant microbes. Forty six percent (46%) of S. aureus isolated were resistant to cloxacillin which is a drug often used for initial and empirical treatment of Staphylococcal infections. This high level of resistance to cloxacillin may pose problems in the treatment of staphylococcal septiceamia. The increasing resistance of S. aureus to cloxacillin, 46% observed as against 40% documented by Angyo et al. (2002) may be due to the widespread abuse of the drug which is usually available in combinations with ampicillin for the treatment of infections in our society and can be obtained over the counter without a prescription. About seventy to ninety percent (70 – 90%) of S. aureus isolates were resistant to other commonly used antibiotics like penicillin, ampicllin, tetracyline and cotrimoxazole. The consequences of using an ineffective drug in severe bacterial infections could be disastrous as this can complicate management and increase morbidity and mortality. Nevertheless, it is interesting to observe that most of the organisms were sensitive to gentamycin, fortum, rocephin, zinnacef, peflacin and vancomycin respectively. Therefore, as gentamiyin and vancomycin are still effective, they can be prescribed for the initial and empirical treatment of septicaemia in our environment pending culture and sensitivity reports.
Although the sensitivity of the organism isolated to the third generation cephalosporin was generally excellent in the present study, the high cost of this group of drugs precludes their use as first choice in the treatment of septicaemia.
CONCLUSIONS
A general overview of the antibiogram of all the bacterial isolates indicates that Gram negative bacteria exhibited a greater level of antimicrobial susceptibility (ranging between 19.8% – 92.3%) than Gram positive bacteria (10% – 87%) to various antibacterial agents employed during the study period. This situation raises serious concern. This suggests a very high resistance gene pool due perhaps to gross misuse and inappropriate usage of the antibacterial agents.
The upsurge in the antibiotic resistance noticed in this study is in agreement with an earlier report by Obseiki-Ebor et al. 1987 where antibiotic abuse and high prevalence of self medication with antibiotics were identified as being responsible for the selection of antibiotic resistant bacterial strains. This piece of work has demonstrated vividly the urgent need for management strategies designed for specific groups of patients with infections in order to maximize therapeutic benefits, cost reduction and possible reduction in the incidence of adverse drug reactions. There is therefore need for usage policy that would be made applicable to the different tiers of our health care providers at the primary, secondary and tertiary levels. This can be done concurrently with sustained enlightenment and media publicity focusing attention on the dangers of high incidence of bacterial resistance to antibacterial agents in general and the ultimate consequences.
Finally, an assessment of the three traditional methods, namely visual inspection (Microscopy), Gram filming and culture for detecting positive blood culture has shown that the latter was the most sensitive, reliable and reproducible. Apart from the identification of the aetiological agents, the antibiogram can also be determined. It can detect some organisms that fail to produce sufficient turbidity to be detected by visual inspection at an early stage of incubation. It also facilitates the early diagnosis of polymicrobial infection and precise judgment/ruling out of suspected contamination of the specimen. Living bacteria could be isolated and distinguished from dead organism. The sensitivity of Gram stain is very close to that of macroscopic (visual) examination (21.2% and 25.4% respectively). This is in tandem to results found by Freeman in 1990. Macroscopic and Gram filming could be adopted for use in rural laboratories that have no culture facilities. Both methods obviate the need for blind subculture and they might be employed as simple sensitive screening method for early detection of organisms in blood streams (Mirret et al., 1982).
REFERENCES
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- Alausa, O. K. and Onile, B. A. (1984). The epidemiological pattern of bacterial septicaemia at University College Hospital, Ibadan. Nigeria Medical Journal 14: 55 – 62.
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