Diseases Associated With the Bacterium

¶ … diseases associated with the bacterium called Proteus vulgaris, outlines its history, explains how the bacterium is transmitted, and its diagnosis, besides discussing prevention of the diseases that proteus vulgaris causes, and their treatment. It also includes an outline of the paper and bibliography.

What is Proteus Vulgaris?

Proteus vulgaris (also known as P. vulgaris) is a rod-shaped, gram negative bacterium that is usually found in the intestinal tracts of animals, but it is sometimes also present in soil, stagnant water, fecal matter, raw meats, and dust. It most commonly causes urinary tract infection such as cystitis (infammation of the ladder) and pyelonephritis (inflammation of the kidney), but may also cause wound infections, sinus and respiratory tract infections.

History

The genus Proteus was first described by the German microbiologist, Gustav Hauser in 1885. It is now known that the genus Proteus has five named species and three unnamed genomospecies but Hauser discovered two of them, i.e., Proteus mirabilis and Proteus vulgaris in his experiments. He did so by noting the swarming nature of the organisms and divided the strains into the two species based on the speed of their ability to liquefy gelatin by discovering that P. vulgaris liquefies gelatin "rapidly," and P. mirabilis does so "more slowly." (O'Hara et al., 2000).

In 1894, Theobald Smith reported the fermentative characteristics of the two species using glucose, sucrose, and lactose and their greatly diminished or complete loss of the ability to liquefy gelatin as the culture aged; in 1919, Wenner and Rettger, while studying the characteristics of the Proteus group of bacteria seconded the discovery by Hauser by noting that P. vulgaris fermented glucose, sucrose, and maltose readily, while P. mirabilis fermented glucose readily and sucrose slowly and did not ferment maltose; After the advent of newer technologies such as DNA-DNA hybridization, Brenner et al. In a1978 study showed for the first time the genetic heterogeneity of P. vulgaris and defined P. vulgaris biogroup 1; with further development of high-resolution and computer technology in the mid-1980s, which made more sophisticated identification of bacteria types, Costas et al. In 1993 further subdivide P. vulgaris into biogroups 2, 3a, and 3b. (Ibid)

How is the Bacterium Spread?

As noted earlier, Proteus vulgaris is present in the gastro-intestinal tracts of animals, including humans as part of normal human intestinal flora but is also sometimes found in the soil, stagnant water, fecal matter, putrified meat and dust. Other habitats of the bacteria include long-term care facilities and hospitals, where this gram-negative bacilli is known to colonize both the skin and oral mucosa of patients and hospital personnel. Infection is primarily spread from these reservoirs. However, Proteus species are not the most common cause of infections and even among the infections caused by the Proteus species of the bacilli, Proteus vulgaris is the cause of a still smaller percentage of infections. For example, the Proteus group of bacteria is the cause of a small percentage of all urinary tract infections (UTI); out of these, Proteus mirabilis causes 90% of all Proteus infections and Proteus vulgaris is the cause of even smaller cases of UTI. This is because P. vulgaris is very rarely found in the faeces and the bacterium usually attacks only those people who have severely compromised immune systems (Senior and Leslie, 1986).

The most common method of the spread of Proteus vulgaris is through direct contact. This can occur, particularly in females, due to the proximity of the urethra to the anus and in unhygienic environments in which the bacteria gets into wounds. People at greater risk of infection are immunosuppressed individuals, those with structural abnormalities of the urinary tract, individuals with multiple prior episodes of UTI, multiple antibiotic treatments, and those who have had urethral instrumentation such as a urinal catheter inserted.

Diagnosis

Diagnosis of the presence of Proteus vulgaris is done through culture tests in the laboratory. Most Proteus strains are lactose negative and demonstrate characteristic swarming motility on agar plates.

The other notable feature of Proteus bacterium is its ability to degrade urea to ammonia, by production of the enzyme urease. This distinguishes them from the other enterics and is used in a simple diagnostic test. Bacteria isolated from urine samples are inoculated onto a nutrient agar containing urea and the indicator phenol red. After overnight incubation, the ammonia produced by Proteus or Providentia raises the pH and changes the colour of the medium from yellow to red (Deacon, n.d.).

Another modern diagnosis system which enables rapid identification of members of the Enterobacteriaceae and other Gram-negative bacteria, including Proteus vulgaris is through the API 20E system. It involves the use of plastic strips consisting of 20 small wells containing dehydrated media components; the bacterium to be tested is suspended in sterile saline and added to each well, then the strip is incubated for 16-24 hours and the color reactions are noted as either positive or negative. The test results are then entered into a computer program identify the bacterium. (Ibid.)

Treatment

The standard treatment of Proteus vulgaris is through a course of antibiotics. However, it should be noted that P. vulgaris (and P. penneri) are more difficult to treat than the commonly occurring Proteus specie -- Proteus mirabilis. Both these strains (P. vulgaris and P. penneri) are resistant to ampicillin and first-generation cephalosporins. However, antibiotic drugs such as Imipenem, fourth-generation cephalosporins, aminoglycosides, TMP/SMZ, and quinolones have been found to be fairly effective against Proteus vulgaris (Gonzales et. al. 2006)

As with other antibiotics, care must be taken against hypersensitive reactions, especially in patients with a history of sensitivity to multiple allergens. In addition, antibiotic therapy requires constant observation for signs of overgrowth of organisms, including fungi. Prolonged treatment also requires periodic check for organ system dysfunction such as the renal, hepatic systems, particularly in infants (Ibid.)

Prevention

Although Proteus vulgaris infection is rare, prevention is always better than cure. For preventing cystitis, it is important to practice proper toilet hygiene. Women and girls must dry themselves from front to back, towards the anus, to avoid leading bacteria from their intestine into their urethra. It is advisable to drink sufficiently, so the bladder remains flushed; people who do not urinate for long periods are likely to suffer from UTI; hence one should urinate at least every three hours. Extra care in hospital hygiene practices would also reduce the spread of Proteus vulgaris infection that are acquired from hospitals. (Macfarlane and Klenerman, 2007)