Understanding Proteus Infections: UTIs & Vulvovaginal Health

Proteus organisms are believed to be responsible for serious infections in humans, being most commonly found in the digestive tract but also in the urinary tract¹ and vagina².

Anyone can become infected with Proteus, but some groups are more at risk than others. Proteus naturally resides in the digestive system and soil, and is very clever at capitalising on weakness to colonise other areas of the body, causing infection.

Some Proteus species are able to develop biofilms, a protective coating on cells that defends the microbes from treatments.

The two worst Proteus species are antibiotic-resistant; therefore, fluid samples should be subjected to susceptibility testing before antibiotic treatment is offered.

Proteus species that cause urinary tract infections (UTIs):

Proteus mirabilis – 90% of infections
Proteus vulgaris

Who gets Proteus UTIs?

Women and people with vaginas who are sexually active have a greater risk of UTIs, and Proteus doesn’t favour anyone in particular. It will infect where it can, being very virulent.

Urinary tract infections are the most common clinical manifestation of infection, with Proteus being responsible for 1-2 per cent of UTIs in healthy women and people with vaginas and about five per cent of hospital-acquired UTIs.

In those who are catheterised or have what’s known as a ‘complicated UTI’, the incidence is 20-45 per cent. In babies, boys see more Proteus infections than girls due to more anatomical abnormalities found in boys than girls.

Is Proteus sexually transmitted?

Proteus is spread via contact with a person already infected, including through sexual contact or from a surface or object that has the bacteria on it.

We can ingest Proteus from food, and the bacteria will quickly spread to the urogenital tract from the intestine, as it’s very agile.

There are plenty of ways for Proteus to infect us, and sexual transmissibility is but one option. Proteus is not considered a sexually transmitted infection.

Symptoms of Proteus urinary tract infection

Bacterial vaginosis
Vaginitis
Urethritis – may be mild
Painful urination (dysuria)
Pus in the urine (cloudy urine, pyuria)
More frequent urination
Urethral discharge
Cystitis – sudden onset
Urinary urgency
Back pain
Kidney stones
Concentrated urine
Small volumes of urine
Blood in the urine
Kidney inflammation
Prostatitis in men
If sepsis, fever, chills, malaise
Nausea
Vomiting
Flank pain

Diagnosis of Proteus infections

Standard lab cultures can easily find Proteus strains, and this bacteria will appear on a comprehensive vaginal microbiome test.

Treatment of a Proteus UTI or vaginitis

Uncomplicated UTIs can be treated with oral antibiotics. Aunt Vadge’s Oral UTI Herbal Blends and Aunt Vadge’s Oral Herbal Medicine AV Blend are also formulated with herbal medicine known to be effective against Proteus species.

If UTI or any urinary tract symptoms are present, choose Aunt Vadge’s Oral UTI Herbal Blends, which contain two bottles: one Bug Mix and one Soothing Mix.

If UTI and vaginitis are present, also concurrently use either Aunt Vadge’s AV Herbal Pessary Blend, or use a vaginal irrigation with the Bug Mix from the oral herbs. A vaginal irrigation is 2ml of herb with 8ml water vaginally using a syringe.

If only vaginitis is a concern, use Aunt Vadge’s Oral Herbal Medicine AV Blend as directed orally, but also use 2ml of herb with 8ml warm water as a vaginal irrigation four times daily or as prescribed by your practitioner.

Aunt Vadge’s AV Herbal Pessary Blend is an appropriate choice for vaginitis caused predominantly by Proteus.

In the case of vaginitis, Proteus bacteria is one of the only bacteria Fluomizin is NOT effective against.

Anyone with a complicated UTI may need longer and/or alternative treatments and have an integrative care team. For support, schedule an appointment with a skilled infection-savvy practitioner.

In severe cases, removal of kidney stones or other surgery may be required due to the impact of Proteus.

Outcomes of Proteus infections

Caught early and treated effectively, Proteus treatment has a solid success rate, but prompt treatment is important.

The risk of Proteus infection for vulnerable populations

People suffering recurrent infections are most at risk, along with those with structural abnormalities of the urinary tract, those who have had instruments inserted into the urethra, and those with a hospital-acquired infection.

People with indwelling catheters are at an increased risk of Proteus infection of 3-5 per cent per day of catheterisation. Proteus infection rates are increased in women and people with vaginas, those with long catheterisations, anyone with an underlying illness, faulty catheter insertions, and lack of antibiotic therapy.

Proteus infection occurs due to the migration of bacteria up the catheter or by migration up the catheter from infected urine.

Understanding the Proteus species and how it infects the urinary tract or vagina

Proteus is a gram-negative bacilli found most often in specific environments, such as hospitals and long-term care facilities. In hospitals, gram-negative bacilli often infect the skin and mouth of staff and patients alike.

Thus, if you live in close contact with someone who works in a hospital, you may come into contact with Proteus more often than the general population.

Why is Proteus so virulent?

Proteus has an extracytoplasmic outer membrane like other gram-negative bacteria. The outer membrane is made of a lipid bilayer, lipoproteins, polysaccharides and lipopolysaccharides.

Also like other gram-negative bacteria, Proteus adheres to its host’s uroepithelial cells using fimbriae. Escherichia coli and P. mirabilis also utilise this attachment method.

After attachment, Proteus starts a series of events in the cells, including secretion of interleukin 6 and interleukin 8. An inflammatory cascade ensues, which, if allowed to enter the bloodstream, can cause sepsis, which is possibly life-threatening.

Proteus causes cell death and the loss of epithelial cells (desquamation). The bacteria produce urease, which is thought to increase the risk of kidney inflammation.

Proteus’ ability to produce urease and alkalise urine (by hydrolysing urea to ammonia) means it creates its own perfect environment in which to survive. The result is struvite kidney stone formation, made of magnesium ammonium phosphate (struvite) and calcium carbonate-apatite.

Struvite stone formation can only occur when ammonia production is increased and the pH of the urine is elevated to decrease the solubility of phosphate – this can only occur when urine is infected with a urease-producing bacteria like Proteus.

Urease metabolises into ammonia and carbon dioxide, making urine rich in ammonia and highly alkaline. Symptoms of struvite stones are uncommon. Typically, those seeking help with a Proteus urinary tract infection will have additional symptoms of flank pain, blood in the urine and alkaline urine with a pH of seven or more.

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