Tenesmus: false urges, causes and treatment

Tenesmus is a painful sensation of incomplete bowel movement, accompanied by urges and straining, despite minimal or no stool. Rectal tenesmus, which affects the rectum and anal canal, is most commonly referred to. Less commonly, the term is applied to the bladder as "vesical tenesmus," but this article focuses on the intestinal variant. The symptom is accompanied by spasms, false urges, and a burning sensation, and can significantly reduce quality of life. [1]

Tenesmus is not a disease in itself; it is a clinical sign of various conditions, ranging from inflammatory bowel disease and proctitis to infections, functional disorders, and rectal tumors. Symptom severity varies from occasional discomfort to constant painful urgency, especially when the distal intestinal mucosa is affected. Understanding the possible causes determines the examination and treatment strategy. [2]

Patients often describe a "feeling of residue" in the rectum that persists after defecation. This sensation is caused either by active inflammation of the mucosa and receptor sensitization, or by impaired coordination of the pelvic floor muscles and sphincters associated with functional disorders. In reality, there may be no content in the rectal ampulla.

Tenesmus is an important symptom of concern, as it accompanies severe forms of acute infectious colitis, including shigellosis with bloody stools, as well as proctitis of various etiologies. If associated "red flags" are present, prompt referral for instrumental diagnostics is required. [4]

Epidemiology

The prevalence of tenesmus as an isolated symptom is difficult to quantify, as it is recorded within the context of various nosologies. In ulcerative colitis, particularly with proctitis and left-sided lesions, urgency and tenesmus are typical manifestations of disease activity. The incidence of ulcerative colitis is estimated at tens per 100,000 population, with an increase in many regions. During exacerbations, the proportion of patients with tenesmus is high. [5]

In infectious colitis, especially shigellosis, tenesmus often occurs along with lower abdominal pain and small amounts of bloody stool. Outbreaks are recorded worldwide, and in recent years, the rise of drug-resistant strains has been highlighted. [6]

In individuals with infectious proctitis associated with sexually transmitted infections such as gonorrhea, chlamydial infection with lymphogranuloma serovars, syphilis, or herpes, tenesmus and rectal pain are common symptoms. The risk is increased in men who have sex with men and in people with multiple sexual partners. [7]

In the group of functional bowel disorders, the proportion of patients with a sensation of incomplete evacuation is higher with concomitant pelvic floor dyssynergia. The effectiveness of biofeedback therapy for this condition has been confirmed by clinical data, which influences the population dynamics of the symptom with targeted treatment. [8]

Reasons

Inflammatory bowel diseases—ulcerative colitis and Crohn's disease with rectal involvement—are among the leading causes of tenesmus. The mechanism is related to mucosal inflammation, swelling, mucus hypersecretion, and increased sensitivity of stretch receptors in the rectum, which leads to false urges. The symptom intensifies during the active stage and subsides during remission. [9]

Acute intestinal infections affecting the distal colon cause tenesmus, most commonly with shigellosis, but also with campylobacteriosis, salmonellosis, and amebiasis. Typical symptoms include small stool volumes mixed with blood and mucus, pain during defecation, and lower abdominal cramps. Isolation of the pathogen is confirmed by stool analysis. [10]

Non-infectious proctitis includes radiation, ischemic, ulcerative, and drug-induced proctitis. Radiation proctitis following pelvic radiation therapy often presents with urgency, bleeding, and tenesmus. Telangiectasias and cicatricial changes are possible in the late phase. [11]

Functional defecation disorders, particularly pelvic floor dyssynergia, lead to ineffective bowel movements with intact colonic propulsion. The patient experiences an obstruction and incomplete evacuation, which is subjectively manifested by tenesmus. Diagnosis relies on anorectal manometry and a balloon expulsion test. [12]

Tumors and benign masses of the rectum, as well as severe hemorrhoids or chronic anal fissures, may be accompanied by false urges to urinate due to local irritation of the mucosa and mechanical obstruction. When combined with bleeding and weight loss, oncologic vigilance and targeted colonoscopy are necessary. [13]

Risk factors

Risk factors for infectious causes include consumption of contaminated food and water, close household contact during outbreaks, travel to regions with high incidence, and poor hand hygiene. Shigellosis is highly contagious and can be transmitted with very low infectious doses. [14]

The risk of infectious proctitis increases with unprotected anal sex, multiple partners, concomitant sexually transmitted infections, and in people with immunodeficiency. Screening tests and prophylaxis are recommended in high-risk groups. [15]

For radiation proctitis, the risk factor is obvious: previous radiation therapy to the pelvic organs. The likelihood and severity of late toxicities are related to the total dose, the irradiation technique, and associated vascular factors. Symptoms can develop months or years after treatment. [16]

Inflammatory bowel disease is caused by a complex set of factors, including genetic predisposition, microbiota, environmental triggers, and medications. Flare-ups can be triggered by nonsteroidal anti-inflammatory drugs, infections, and stress. [17]

Pathogenesis

The key link in the pathogenesis of tenesmus is inflammation and sensitization of afferent nerve endings in the rectal mucosa. Inflammatory mediators lower the activation thresholds of mechanoreceptors, so even minimal bowel movements or swelling are interpreted by the brain as a need to defecate. This results in the sensation of "residue" when the ampulla is empty. [18]

In infectious colitis, cytotoxins from pathogens and inflammatory processes in the distal colon enhance motor and pain responses. Shigellosis is characterized by frequent small bowel movements and tenesmus due to severe mucosal inflammation with superficial ulcers. [19]

In radiation proctitis, early reactions are associated with damage to the epithelium and microvessels, while late reactions are associated with ischemia, telangiectasias, fibrosis, and impaired regeneration. These changes maintain chronic urgency and discomfort, resistant to simple symptomatic measures. [20]

Pelvic floor dyssynergia disrupts the coordination of the abdominal muscles, the levator ani muscle, and the anal sphincter. Instead of reflex relaxation during straining, a paradoxical contraction of the sphincter occurs. This leads to a feeling of incomplete evacuation and repeated, fruitless attempts at defecation. [21]

Symptoms

The main symptom is frequent, false urges with a feeling of incomplete evacuation, painful straining, and minimal stool. This is often accompanied by pain, burning in the anal canal, mucus or blood, and tenderness during digital examination. The nature of the stool and its presence helps differentiate the causes. [22]

Infectious colitis, especially shigellosis, is characterized by frequent small bowel movements containing blood and mucus, fever, cramping pain in the lower abdomen, and severe tenesmus. Stools are often scanty, but the frequency of bowel movements is frequent, which exhausts the patient. [23]

Proctitis, including ulcerative proctitis, may be accompanied by bloody discharge, rectal pain, and increased urgency in the morning and after meals. A history of radiation therapy and a gradual increase in bleeding and discomfort indicate a radiation-related cause for the symptoms. [24]

Functional disorders are characterized by prolonged straining, a feeling of "blockage," and the need for digital assistance or special positions for bowel movements. Pain is less associated with inflammation and more with muscle strain, and is often associated with constipation. [25]

Forms and stages

Based on duration, tenesmus is classified as acute, occurring during infections or acute inflammatory episodes, and chronic, occurring during ongoing proctitis, inflammatory bowel disease, or dyssynergia. Acute symptoms typically correlate with disease activity and subside after etiotropic treatment. [26]

Based on severity, pain is classified as mild and episodic, moderate with regular urgency, and severe, in which the urge is repeated and disrupts sleep, eating, and social activity. Stratification helps determine the intensity of therapy and indications for hospitalization. [27]

Based on etiology, inflammatory, infectious, radiation, functional, and neoplastic variants are conventionally distinguished, as the set of diagnostic tests and treatment tactics differ between the groups. Each profile has its own diagnostic algorithm. [28]

In the context of inflammatory bowel diseases, it is practical to rely on activity indices and the extent of the lesion, since when localized in the rectum, the symptom of tenesmus occurs more frequently and often responds better to local therapy with suppositories. [29]

Complications and consequences

Without treatment, persistent tenesmus leads to pain, irritability, sleep disturbances, and social maladjustment. Frequent, unsuccessful attempts to defecate increase perianal swelling and skin irritation, increasing the risk of fissures and secondary infection. [30]

Severe infectious colitis can cause dehydration, electrolyte disturbances, anemia due to blood loss, and, in vulnerable patients, septic complications. Some strains exhibit antibiotic resistance, requiring microbiological verification and appropriate treatment selection. [31]

In patients with inflammatory bowel disease, complications of active proctitis may include increased bleeding, anemia, severe urgency with incontinence, and decreased quality of life. Long-term inflammation increases the risk of local structural changes. [32]

Late-stage radiation proctitis is fraught with persistent bleeding, telangiectasias, stenosis, and chronic pain. In some cases, endoscopic coagulation techniques and topical agents to reduce contact bleeding are required. [33]

Diagnostics

1. Anamnesis and physical examination with digital rectal examination are performed to determine the duration and frequency of urination, blood and mucus, pain, relationship with food, fever, sexual practices, and previous radiation therapy; examination helps identify fissures, hemorrhoids, and tumor-like formations. [34]
2. General clinical tests: complete blood count to assess anemia and signs of inflammation, C-reactive protein and erythrocyte sedimentation rate to assess inflammatory activity, biochemical profile as indicated. [35]
3. Stool for pathogen: culture and molecular panels if bacterial etiology is suspected, C difficile toxin and gene test for antibiotic-associated diarrhea, parasitological tests if risk exists. [36]
4. Caloric calprotectin: helps differentiate inflammatory bowel disease from functional disorders, sensitive to mucosal inflammation; useful for routing to endoscopy. [37]
5. Testing for sexually transmitted infections in patients with proctitis symptoms and associated risk factors: screening for gonorrhea, chlamydia, syphilis, and human immunodeficiency virus, including other exposed sites. [38]
6. Endoscopy: rectoscopy for distal symptoms to verify proctitis, assess activity and take biopsies; colonoscopy if more proximal lesion, neoplasia or inflammatory bowel disease is suspected. [39]
7. Imaging: computed tomography or magnetic resonance imaging for complications, suspected tumor or extraintestinal complications, and severe pain and fever. [40]
8. Physiological tests for suspected pelvic floor dyssynergia: anorectal manometry and balloon expulsion test, defecography if indicated. [41]

Table 1. Red flags requiring urgent diagnosis or referral

Sign	Why is it important?	Act One
Blood in the stool in adults, especially after 50 years	Risk of neoplasia	Urgent endoscopy
Weight loss, anemia, fever	Systemic inflammation or tumor	Extended laboratory and instrumental evaluation
Post-radiation history with increasing bleeding	Radiation proctitis is possible	Endoscopic evaluation and hemostasis
Severe pain and frequent small bowel movements	Severe infectious colitis is possible	Stool culture and initial therapy as indicated
[42]

Table 2. Primary laboratory and fecal tests

Test	What does it show?	When to prescribe
Complete blood count	Anemia, leukocytosis	For bleeding and systemic symptoms
C-reactive protein and erythrocyte sedimentation rate	Inflammatory activity	If inflammatory processes are suspected
Fecal calprotectin	Marker of intestinal inflammation	To differentiate inflammatory and functional causes
Stool culture, PCR panels	Etiology of bacterial colitis	In case of fever, blood in stool, epidemiological factors
[43]

Differential diagnosis

A combination of history, systemic symptoms, epidemiological factors, and stool data helps differentiate infectious colitis from inflammatory bowel disease. Acute fever, epidemiological associations, and a rapid onset are typical of infections, while a prolonged, fluctuating course is typical of inflammatory bowel disease. Fecal calprotectin and endoscopy with biopsy are crucial. [44]

Proctitis associated with sexually transmitted infections is differentiated from ulcerative proctitis and radiation-induced changes based on the patient's medical history, infection test results, and endoscopic findings. If lymphogranuloma Veneris is suspected, an extended course of doxycycline is considered, which differs from the standard treatment for uncomplicated chlamydial infection. [45]

Functional bowel disorders are distinguished by the absence of signs of inflammation, normal fecal calprotectin levels, and characteristic physiological test results. Biofeedback therapy is more effective than laxatives in this case, provided the transit rate is normal, which serves as indirect diagnostic confirmation. [46]

Tumors and precancerous polyps are excluded by endoscopy in patients with bleeding, anemia, changes in bowel habits, and a concerning age or family history. Guidelines for "urgent" referrals are developed for primary care and help prevent colorectal cancer from being missed. [47]

Table 3. Distinctive features of the main groups of causes

Group	Start	Character of stool	Systemic signs	Key test
Infectious colitis	Spicy	Small portions, blood and mucus	Fever, myalgia	Stool culture, PCR
Ulcerative proctitis	Gradual	Blood, mucus, morning urgency	Anemia is possible	Endoscopy with biopsy
Radiation proctitis	Delayed after radiation therapy	Bleeding, pain	Often without fever	Endoscopy, anamnesis
Pelvic floor dyssynergia	Long time	Small stool, "block"	No systemic signs	Manometry
[48]

Treatment

Treatment is aimed at eliminating the cause and relieving symptoms. For infectious colitis, the mainstay is rehydration and etiotropic therapy as indicated, taking into account local resistance. For shigellosis, antibiotics are indicated for moderately and severely ill patients, those in risk groups, and those with bloody stools. The choice is determined based on test results and local recommendations. [49]

For ulcerative proctitis, topical 5-aminosalicylates in the form of suppositories or enemas are highly effective, reducing urgency and bleeding. Topical corticosteroids, including rectal budesonide, are an alternative. If the response is insufficient, systemic steroids and biologic agents or Janus kinase inhibitors are used depending on the disease profile. [50]

For infectious proctitis associated with sexually transmitted infections, empirical treatment is prescribed, with subsequent adjustments based on test results. Testing for human immunodeficiency virus and syphilis is performed, and prophylaxis against human immunodeficiency virus is considered. For suspected lymphogranuloma Veneris, an extended course of doxycycline is recommended. [51]

For pelvic floor dyssynergia, the treatment of choice is biofeedback therapy monitored by manometry and electromyography, which is more effective than standard laxatives when colon motility is preserved. Additional treatments include training in correct bowel posture, osmotic stool support, and training in a regular routine. [52]

Symptomatic measures for mild cases include warm sitz baths, local anesthetics for fissures, and dietary modifications with adequate fluid intake and a gradually titrated amount of dietary fiber. With active inflammation, excess coarse fiber can increase discomfort, so dietary adjustments are individualized. [53]

Table 4. Therapy by main etiological groups

Cause	First line	Alternatives and escalation
Shigellosis and other bacterial colitis	Rehydration, antibiotics according to indications and sensitivity	Correction of therapy based on the results of culture and resistance
Ulcerative proctitis	Mesalamine suppositories daily	Rectal budesonide, systemic steroids, biologics, Janus kinase inhibitors
Sexually transmitted infectious proctitis	Empirical therapy covering gonococcus and chlamydia, testing for concomitant infections	Extended doxycycline for suspected lymphogranuloma veneris
Pelvic floor dyssynergia	Biofeedback therapy	Osmotic laxatives as support, teaching posture and routine
[54]

Table 5. Local remedies for proctitis and the evidence base

Means	Form	Commentary on effectiveness
Mesalamine	Suppositories, enemas	First line treatment for ulcerative proctitis with good urgency control
Budesonide	Rectal forms	Alternative for intolerance or inadequate response to mesalamine
Sucralfate	Retention enemas	Useful for radiation proctitis to reduce bleeding
Endoscopic hemostasis	Argon plasma coagulation	For persistent bleeding due to radiation injury
[55]

Prevention

Prevention of infectious causes includes hand hygiene, safe food storage and preparation, avoidance of unsafe water, and outbreak control measures in organized settings. For enteric infections, early microbiological confirmation is important for targeted therapy and prevention of dissemination. [56]

Prevention of infectious proctitis involves barrier protection during anal sex, regular testing in at-risk groups, awareness of symptoms, and timely referral. For cancer patients undergoing radiation therapy, surveillance programs with early detection of radiation toxicities and correction of bleeding risk factors are beneficial. [57]

Forecast

The prognosis is determined by the cause. In infectious colitis, with timely rehydration and appropriate antibacterial therapy, there is a tendency for rapid improvement, although with resistant strains, protracted cases are possible. In ulcerative proctitis, local anti-inflammatory therapy often ensures remission and control of urgency. [58]

With radiation proctitis, symptoms can persist for a long time, requiring a combined approach with topical medications and endoscopic methods. For functional disorders, targeted pelvic floor rehabilitation provides lasting symptom reduction in most patients. [59]

FAQ

• Is this dangerous in itself or just as a symptom?

The danger is determined by the cause. Tenesmus alone indicates irritation or inflammation of the rectum, but when combined with blood, fever, weight loss, or anemia, urgent examination and endoscopy are necessary. [60]

• Is it possible to treat with diet and antispasmodics alone?

For mild functional complaints, dietary correction and symptomatic support help, but if there are signs of inflammation or infection, this is not enough - etiotropic therapy and observation are required. [61]

• When is a colonoscopy needed?

If there is blood in the stool, anemia, weight loss, age-related risk factors, or persistent symptoms without explanation, endoscopic examination with biopsy is indicated to exclude inflammatory and neoplastic causes. [62]

• What is the difference between proctitis associated with sexually transmitted infections?

Typically begins acutely with pain, discharge and tenesmus, requiring testing for gonorrhea, chlamydial infection, syphilis and human immunodeficiency virus and specific therapy, sometimes longer courses of antibiotics if lymphogranuloma of Venus is suspected. [63]