Urine Drug Concentration & Clinical Efficacy
Antimicrobial drugs must achieve an adequate urine concentration, which must be maintained for a sufficient time for a drug to be effective in treating UTI.16 It has been suggested that clinical efficacy is observed when the urine drug concentration is maintained at a concentration 4-fold higher than the isolates MIC throughout the time between doses.9
Experimental studies in rats have shown that the time for which the plasma drug concentration exceeds the isolates MIC correlates to the magnitude of bacterial colony count reduction the longer the time for which the drug concentration remained above the MIC, the lower the urine colony counts.12 Successful eradication of bacteria within the renal parenchyma or urinary bladder wall is correlated to the plasma, not urine, drug concentration.
When prescribing time-dependent antibiotics, shortening the interval between drug administration is the most effective method to allow the tissue/urine drug concentration to exceed the MIC for the majority of the dosing interval.
- Drug elimination follows first-order kinetics, where 50% of the drug is lost in 1 half-life.
- In contrast, doubling the dose would only add 1 half-life to the dosing interval.
- To add 2 half-lives to the dosing interval, the initial dose would have to be increased 4-fold. The peak serum drug concentration achieved by this approach may exceed the window of safety, producing adverse drug effects.
What If I Don’t Go To The Doctor
What happens when UTIs are left untreated? Contrary to popular belief, your immune system is often able to clear a UTI on its own. Studies have found that 25-42% of women are able to recover from an uncomplicated UTI without antibiotics.
But that means a majority of UTIs do not go away on their own. If left untreated, they can lead to continued discomfort and other more serious health issues, such as kidney damage or a severe infection. Therefore, treatment is recommended.
“Physicians tailor care plans to each patient, and there is no sole treatment for everyone,” says Stanford physician Kim Chiang, MD. During your visit, feel free to ask in-depth questions, particularly if a non-recommended antibiotic is prescribed.
This is the fifth post in the series Understanding UTIs. The goal of this seven-part series is to provide easy-to-understand, scientifically grounded information about UTIs. Patients referenced are composites, compiled from actual patient experiences.Data on medications used for UTIs were extracted from the National Disease and Therapeutic Index, a nationally representative physician survey produced by IQVIA.
An Ounce Of Prevention
Unfortunately, most UTIs are not completely preventable, and are caused by differences in the structure or function of the urinary tract and immune system. But there are things you can do to keep healthy. For example, stay hydrated to increase urine production and flush out unwanted bacterial intruders. Good hygiene is also important, but scrubbing away at delicate genital tissues can damage them and create portals for bacteria. Clean your genital area gently with mild soap and water. Postmenopausal women may benefit from vaginal estrogen cream. Finally, eating cranberries and urinating after having sex havent been proven to have major benefits, but arent likely to hurt, either.
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About the Author
Lisa Bebell, MD, Contributor
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What Is Kidney Infection
Infection in the urinary tract can involve the lower tract especially the bladder , prostate or the upper tract and kidney . It is usually a bacterial infection. The disease occurs in roughly three to seven of every 10,000 people in the United States. The occurrence in pregnant women is about 2 percent. It is readily treatable if diagnosed early.
A bacteria called Escherichia Coli causes about 90 percent of kidney infections. The bacteria migrate from the genitals through the urethra into the bladder and up the tubes that connect the bladder to the kidneys.
Some bacteria, such as staphylococcus infections, can enter the kidneys from the bloodstream.
Accurate Diagnosing Of A Uti
Can you self-diagnose a UTI? First of all, read why OTC UTI test strips could be inaccurate in your case.
Moreover, in a recent study, less than 50% of women who reported UTI symptoms to their physician truly had a urinary tract infection.
The most accurate predictors of a true UTI are the combination of urgency to urinate, burning during urination, and pyuria .
The same study suggests that more physicians should perform wet mount microscopy test to look for white cells in the urine before prescribing antibiotics for UTI.
Have you noticed blood in your urine, cloudy urine or a funny smell to your urine? These are some symptoms that are indicative of a UTI, especially if they have been happening only for a short time. These symptoms may be more predictive than lower abdomen pain and burning with urination, which is also common with bladder inflammation that is not due to a UTI.
Important: if you have recurring blood in your urine and no other signs of a UTI, let your doctor know right away as this could be a sign of a bladder tumor that should be treated right away.
Therefore, whenever you are offered antibiotics for UTI, always ask for a urine culture test or wet mount microscopy test.
Always pay attention to your UTI symptoms, even after you finish your antibiotic treatment. If you have just finished a course of antibiotics but your symptoms still linger on, read this interview with a urologist explaining why antibiotics may not work for your UTI.
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Whats The Difference Between A Urinary Tract Infection And Bladder Infection
A urinary tract infection is a more general type of infection. There are many parts of your urinary tract. A UTI is a term for an infection that takes place throughout the urinary tract. A bladder infection, also called cystitis, is a specific infection. In this infection, bacteria makes its way into the bladder and causes inflammation.
Not all urinary tract infections become bladder infections. Preventing the spread of the infection is one of the most important reasons to treat a UTI quickly when you have symptoms. The infection can spread not only to the bladder, but also into your kidneys, which is a more complicated type of infection than a UTI.
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How Are Urinary Abnormalities Diagnosed
Its important for a doctor to rule out any underlying problems in the urinary system when a child gets UTIs repeatedly. Kids with recurrent infections should see a pediatric urologist to see what is causing the infections.
Some problems can be found before birth. Hydronephrosis that develops before birth can be seen in an ultrasound as early as 16 weeks. In rare cases, doctors may consider neonatal surgery if hydronephrosis affects both kidneys and is a risk to the fetus. Most of the time, though, doctors wait until after birth to treat the condition, because almost half of all cases seen prenatally disappear by the time a baby is born.
Doctors will closely watch the blood pressure of a newborn thought to have hydronephrosis or another urinary system abnormality, because some kidney problems can cause high blood pressure. Another ultrasound may be done to get a closer look at the bladder and kidneys. If the condition appears to be affecting both kidneys, doctors usually will order blood tests to check kidney function.
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Chronic Nonbacterial Prostatitis/chronic Pelvic Pain Syndrome
It has been widely reported that more than 90 percent of men with prostatitis meet the criteria for chronic nonbacterial prostatitis/chronic pelvic pain syndrome .10 However, these estimates come from urologic referral centers and are likely to over-represent more complex cases and under-represent more straightforward cases of acute and chronic bacterial prostatitis. Because of these referral biases, the true incidence and prevalence of these syndromes are unknown.
The treatment of this condition is challenging, and there is limited evidence to support any particular therapy. Given the high rate of occult prostatic infection, an antibiotic trial is reasonable, to see if the patient responds clinically. Because Chlamydia trachomatis, Ureaplasma urealyticum and Mycoplasma hominis have been identified as potential pathogens, treatment should cover these organisms.
Question : What Are Preferred Antibiotics For The Treatment Of Uncomplicated Cystitis Caused By Cre
Recommendation: Ciprofloxacin, levofloxacin, trimethoprim-sulfamethoxazole, nitrofurantoin, or a single-dose of an aminoglycoside are preferred treatment options for uncomplicated cystitis caused by CRE. Standard infusion meropenem is a preferred treatment option for cystitis caused by CRE resistant to ertapenem but susceptible to meropenem, when carbapenemase testing results are either not available or negative.
Rationale: Clinical trial data evaluating the efficacy of most preferred agents for CRE cystitis are not available. However, as these agents achieve high concentrations in urine, they are expected to be effective for CRE cystitis, when active. Some agents that are listed as alternative options for ESBL-E cystitis are recommended as preferred agents for CRE cystitis. These agents are preferably avoided in treatment of ESBL-E cystitis in order to preserve their activity for more invasive infections. They are preferred agents against CRE cystitis because there are generally fewer treatment options against these infections.
Meropenem is a preferred agent against CRE cystitis for isolates that remain susceptible to meropenem, since most of these isolates do not produce carbapenemases . Meropenem should be avoided if carbapenemase testing is positive, even if susceptibility to meropenem is demonstrated.
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Intracellular Bacteria Localization By Laser Confocal Microscopy
Although all the evaluated UPECs were able to enter the eukaryotic cells, confirmation and localization of intracellular bacteria was performed by confocal laser scanning microscopy . Four strains were tested, two of which were negative for the presence of IBC in urine desquamated cells .
After image acquisition and their subsequent analysis, all the strains were observed in small groups, rather than dispersed in the cytoplasm .
Figure 4E. coli invasion assay in T24 cells. The images represent the xyz stacks obtained with CLSM. Maximum intensity z-projections are shown in the central panel, upper and left are zx and zy, respectively. In red actin staining , in blue DNA , and in green UPEC . UPEC 7, the intracellular bacteria are observed in groups inside the eukaryotic cell resembling IBC. UPEC 144, intracellular bacteria are observed in big groups in a perinuclear localization. UPEC 172, in this case the intracellular bacteria are dispersed in the cytoplasm of the eukaryotic cell. Severe damage is observed as the cells had their membrane damaged and the presence of philopodia this is in agreement with cytotoxicity assay as UPEC 172 had one of the highest values. UPEC 174, disperse intracellular bacteria is observed.
How Can I Make Sure My Kidney Infection Is Completely Gone
If you recently had a kidney infection, the health care professional will often repeat urine cultures after your treatment ends to make sure your infection has completely gone away and has not come back. If a repeat test shows infection, you may take another round of antibiotics. If your infection comes back again, he or she may prescribe antibiotics for a longer time period.
If your health care professional prescribes antibiotics, take all of the antibiotics as prescribed and follow the advice of the health care professional. Even if you start to feel better, you should finish all of your medicine.
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Use Of Antibiotics For Treating Utis In Dogs And Cats
Dr. Foster is an internist and Director of the Extracorporeal Therapies Service at Friendship Hospital for Animals in Washington, D.C. He has lectured around the world on various renal and urinary diseases and authored numerous manuscripts and book chapters on these topics. He is the current president of the American Society of Veterinary Nephrology and Urology.
Urinary tract infections are common in small animal practice it has been reported that up to 27% of dogs will develop infection at some time in their lives.1
Most UTIs are successfully treated with commonly used drugs, dosages, and administration intervals. However, infections can be challenging to effectively treat when they involve the kidneys and prostate . In addition, it can be difficult to create an appropriate antibiotic prescription in patients with kidney disease due to reduced drug clearance.
Understanding drug pharmacokinetics and pharmacodynamics is essential when determining the most effective antibiotic therapy. In addition, successful antimicrobial therapy requires appropriate choice of antibiotic, including dose, frequency, and duration .
Get Strep Throat Treatment Online
If you or your child are experiencing throat pain, painful swallowing, and other common strep throat symptoms, we have good news: you dont need to visit your doctors office for strep throat antibiotics.
Instead, you can schedule an online appointment with one of the trusted doctors at PlushCare. If your doctor thinks strep throat antibiotics are right for you, they can send an electronic prescription to your local pharmacy.
What Does It Mean If You Have Recurring Utis
Recurrent urinary tract infections are widespread. One study found that 44% of women who experience acute uncomplicated cystitis will have a recurrence later that year, usually within three months from the initial episode. Most providers define recurrent UTIs as two or more infections in six months or three episodes or more over a year .
Recurrent UTIs usually do not indicate a failure of the first treatment, though the same strain of germs may have reinfected you. If your last infection happened recently, your healthcare provider might ask for a urine culture to see if the drug was active. A UTI is considered a relapse of the same infection if the recurrence happens within two weeks of a previous episode .
Home Remedies For Utis
Until there are more advancements in UTI treatment, antibiotics remain the most effective standard treatment. However, prescription medication doesnt have to be the only line of defense.
Along with standard therapy, you can incorporate home remedies to feel better sooner and reduce the likelihood of recurrent infections.
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Antibiotics For A Kidney Infection
Antibiotics are the main treatment for a kidney infection, and are usually the only treatment thats needed.
If your doctor strongly suspects that you have a kidney infection based on your symptoms, you may be immediately prescribed an antibiotic that targets the most common bacteria that cause kidney infections.
Once your lab test results are in, your doctor may adjust your prescription based on the exact type of bacteria causing your infection. These antibiotics may be taken by mouth or IV.
Usually, your symptoms will start to get better within a few days of starting on antibiotics. But even if you feel better, its important to take the full course of antibiotics youve been prescribed.
Depending on the specific drug you take, your course of antibiotics will typically last for 5 to 14 days. Taking the full course ensures that all bacteria causing your infection are eliminated.
Antibiotics used to treat kidney infections include:
When Do I Really Need Antibiotics For A Sinus Infection
When do I really need antibiotics for a sinus infection? is a question many patients have when suffering from bothersome sinus and allergy problems. While sinus infections can be quite painful, antibiotics often do not help in treating the condition.
Sinus infections affect approximately 37 million people in the U.S. each year and can be caused by:
- Nasal polyps or deviated septum causing nasal obstruction
The majority of sinus infections are viral in nature, and antibiotics do not cure viral infections. Taking antibiotics for viral infections also will not:
- Keep you from being contagious to others
- Relieve symptoms or make you feel better
In order to distinguish a bacterial sinus infection from an infection caused by a virus or other contributing factor, your doctor will observe your symptoms and possibly conduct other tests, such as a CT scan or cultures.
Antibiotics are only effective on bacterial infections, and even in cases involving bacteria, the body can often cure itself of mild or moderate infections within a few days.
Check If It’s A Urinary Tract Infection
Symptoms of a urinary tract infection may include:
- pain or a burning sensation when peeing
- needing to pee more often than usual during the night
- pee that looks cloudy, dark or has a strong smell
- needing to pee suddenly or more urgently than usual
- needing to pee more often than usual
- lower tummy pain or pain in your back, just under the ribs
- a high temperature, or feeling hot and shivery
- a very low temperature below 36C
What Happens If I Have A Multidrug
Some strains of bacteria are now resistant to all of the most commonly used antibiotics. When UTIs recur or dont go away with treatment, urine samples are usually tested at a microbiology lab, and if resistant organisms are discovered they are often found to be ESBL E. coli or ESBL Klebsiella. If you have a UTI with either of these resistant bacteria, you will probably be treated in hospital by an infectious disease doctor and their team. They will often prescribe a specific antibiotic via an intravenous drip known to be active against ESBL- producing bacteria such as a carbapenem antibiotic. These are considered last resort antibiotics which are kept especially for those highly resistant bacterial infections.
If you have an antibiotic-resistant UTI, youre not alone. There are many different support groups online where people suffering with resistant UTIs can help one another.
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What Type Of Bacteria Usually Cause Urinary Tract Infections
The most common bacterial cause of UTIs are E coli. These bacteria usually live harmlessly in the gut of healthy people but can cause problems if they get into the bladder or other parts of the urinary tract. Uncomplicated infection of the bladder, also called cystitis, is common and can be very painful.
Some strains of E. coli bacteria have begun to produce enzymes called extended-spectrum beta-lactamases . These can make the bacteria resistant to certain antibiotics, and so the bacteria continue to multiply and spread. This causes more severe infection which becomes much more difficult to treat. Another type of bacteria which often causes antibiotic resistant UTIs is ESBL klebsiella pneumoniae. You can read more about extended-spectrum beta-lactamase-producing bacteria here.
E. coli belongs to the Enterobacteriaceae family of Gram-negative bacteria. This family of bacteria also include klebsiella pneumoniae and enterobacter cloacae. The Enterobacteriaceae family can all cause UTIs and are often treated with the beta-lactam antibiotic, carbapenem, for which there are specific ESBL enzymes. The carbapenem resistant Enterobacteriaceae that have developed, have become a real risk to health as the main antibiotic becomes useless and their presence increases in hospitals and care settings.