Kobra Salimiyan rizi; Hadi Farsiani; Mohammad Momen Ghalibaf
Abstract
Today, human bloodstream infections (BSIs) are recognized as a major cause of morbidity and mortality worldwide. The bacteria, responsible for bacteremia, are usually identified in diagnostic clinical laboratories, using blood cultures. True bacteremia is defined as a positive blood culture (>15 CFU/mL), ...
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Today, human bloodstream infections (BSIs) are recognized as a major cause of morbidity and mortality worldwide. The bacteria, responsible for bacteremia, are usually identified in diagnostic clinical laboratories, using blood cultures. True bacteremia is defined as a positive blood culture (>15 CFU/mL), with signs and symptoms of infection (e.g., fever and chills). A wide range of bacteria can cause true bacteremia and some bacterial isolates from BSIs may be responsible for contamination. Gram-positive bacilli, such as Bacillus species, and coryneform bacteria are suspected sources of contamination in blood cultures. However, in certain patients, such as immunocompromised patients and intravenous drug users, gram-positive bacilli can act as a true pathogen. Therefore, it is important to know when gram positive bacilli act as a true pathogen and when they act as contamination. So, the rapidly diagnosis of true pathogens and appropriate treatment play a very important role in controlling infection with these bacteria. Effective measures are especially important in patients with an underlying disease or an immunocompromised status. In this article, we reviewed the literature on common Gram-positive rod-shaped bacteria, which were isolated from blood cultures and were suspected to be true pathogens or contaminants.
Kobra Salimiyan rizi; Kiarash Ghazvini; Hadi Farsiani
Abstract
Enterobacter spp. is a gram-negative environmental bacterium, which belongs to the Enterobacteriaceae family and is found in water, sewage, soil, and plants. These bacteria are common among humans and animals, and the most frequently isolated species is Enterobacter cloacae. The species of this genus ...
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Enterobacter spp. is a gram-negative environmental bacterium, which belongs to the Enterobacteriaceae family and is found in water, sewage, soil, and plants. These bacteria are common among humans and animals, and the most frequently isolated species is Enterobacter cloacae. The species of this genus are often opportunistic pathogens with expanding significance in nosocomial infections, particularly in neonates, immunocompromised patients in intensive care units, emergency sections, skin and soft tissue infection wards, and urology wards. With the unexpected and rapid increase in antibiotic resistance in various bacterial species, there has been a new alarm for the health of the human community. Enterobacter species cause pneumonitis, bacteremia, post-neurosurgical meningitis, neonatal meningitis, skin and soft tissue infections, and urinary tract infections. Some of the main risk factors for the occurrence and dissemination of Enterobacter spp. infections are poor hand hygiene, crowding, low birth weight, premature birth, intubation of patients, prolonged hospital stay, contaminated infant formula, intravenous feeding, use of extended-spectrum antibiotics and use of intravenous catheters.
Kobra Salimiyan Rizi; Hadi Farsiani; Saeid Amel Jamehdar; Mahboubeh Mohammadzadeh
Abstract
Elizabethkingia meningoseptica is an emerging nosocomial gram-negative, rod-shaped pathogen in patients with underlying diseases. This bacterium is also considered to be a major pathogen in hospitalized patients. Some of the main risk factors for E. meningosepticum infections include immunosuppression ...
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Elizabethkingia meningoseptica is an emerging nosocomial gram-negative, rod-shaped pathogen in patients with underlying diseases. This bacterium is also considered to be a major pathogen in hospitalized patients. Some of the main risk factors for E. meningosepticum infections include immunosuppression (e.g., end-stage hepatic and renal diseases) and prematurity in neonates. Furthermore, E. meningosepticum could cause pneumonia, endocarditis, and bacteremia in adults. The uncommon resistance pattern of this bacterium, as well as its intrinsic resistance to colistin, makes the treatment of the associated infections challenging unless the susceptibility patterns are available. In this article, we have presented the first case of pulmonary coinfection with multidrug-resistant (MDR) Acinetobacter spp. and E. meningoseptica in Iran. A 20-year-old female patient was admitted to our hospital with tetralogy of fallot as an underlying disease since childhood. The patient underwent cardiac surgery. On the third postoperative day (POD), the patient developed lung infection and left-lung collapse. Antibiotic therapy was initiated for MDR Acinetobacter spp. obtained from her primary culture of tracheal discharges. When fever persisted in the patient, the secondary culture of her tracheal discharges was observed to be positive for E. meningoseptica. In this case report, no clinical correlations were observed between the E. meningoseptica isolated from respiratory secretions and the primary respiratory infection, suggesting that E. meningoseptica is an indicator of severe underlying diseases rather than an actual pathogen.
Kobra Salimiyan Rizi; Hadi Farsiani; Kiarash Ghazvini; Masoud Youssefi
Abstract
Rothia dentocariosa (R. dentocariosa) is a gram-positive bacterium, which is a microorganism that normally resides in the mouth and respiratory tract. R. dentocariosa is known to involve in dental plaques and periodontal diseases. However, it is considered an organism with low pathogenicity and is associated ...
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Rothia dentocariosa (R. dentocariosa) is a gram-positive bacterium, which is a microorganism that normally resides in the mouth and respiratory tract. R. dentocariosa is known to involve in dental plaques and periodontal diseases. However, it is considered an organism with low pathogenicity and is associated with opportunistic infections. Originally thought not to be pathogenic in humans, R. dentocariosa was first described to cause infections in a 19-year-old female with periappendiceal abscess in 1975. The most prevalent human infections caused by R. dentocariosa include infective endocarditis, bacteremia, endophthalmitis, corneal ulcer, septic arthritis, pneumonia, and peritonitis associated with continuous ambulatory peritoneal dialysis. Three main factors have been reported to increase the risk of the cardiac and extra-cardiac infections caused by R. dentocariosa, including immunocompromised conditions, pre-existing cardiac disorders, and poor oral hygiene. Peritoneal dialysis (PD) may induce peritonitis presumably due to hematogenous spread from gingival or periodontal sources. This case study aimed to describe a former PD patient presenting with peritonitis. Oral hygiene is a basic principle in PD patients for the prevention of peritonitis. It is speculated that our patient might have had an occult oral source of R. dentocariosa.