Recognizing and Treating Bacillary Dysentery in Children

Bloody diarrhea in a child is alarming for any parent or caregiver. When accompanied by mucus, fever, and severe abdominal cramping, it could indicate bacillary dysentery-a highly contagious gastrointestinal infection caused by Shigella bacteria. Understanding this condition is essential for paediatric nurses, as prompt recognition and management can prevent serious complications and even save lives.

What is bacillary dysentery? 🔗

Bacillary dysentery, also called shigellosis, is an acute intestinal infection that primarily affects the colon. Unlike other diarrheal illnesses, shigellosis causes inflammation and ulceration of the intestinal mucosa, resulting in its characteristic bloody stools mixed with mucus and pus. The infection is particularly concerning in young children, who experience more severe and prolonged illness compared to healthy adults.

Globally, Shigella species are responsible for millions of diarrheal episodes annually. According to the Institut Pasteur, approximately 200,000 deaths occur each year worldwide, with 65,000 of these among children under five years of age. Children younger than five have the highest infection rates, making this a critical topic for paediatric healthcare providers.

The causative agent: Shigella bacteria 🔗

Shigella is a gram-negative, non-motile bacterium belonging to the Enterobacterales order. Four main species cause human disease, each with distinct characteristics and severity profiles.

The four Shigella species 🔗

Shigella dysenteriae (Serogroup A) causes the most severe form of dysentery. It produces Shiga toxin, which can lead to life-threatening complications including hemolytic uremic syndrome. Though less common in developed countries, it remains endemic in parts of Africa and South Asia.

Shigella flexneri (Serogroup B) is the most common cause of shigellosis worldwide and is endemic in low- and middle-income countries. It frequently causes bloody diarrhea and is associated with reactive arthritis in genetically susceptible individuals.

Shigella boydii (Serogroup C) is relatively rare and primarily found in the Indian subcontinent.

Shigella sonnei (Serogroup D) is the predominant species in high-income countries and typically causes milder illness with watery diarrhea rather than severe dysentery.

How does Shigella spread? 🔗

Shigella transmission occurs primarily through the fecal-oral route. What makes this bacterium particularly dangerous is its extremely low infectious dose-as few as 10 to 100 organisms can cause disease. This explains why shigellosis spreads so rapidly in settings like daycare centres and schools.

Common transmission routes include direct contact with infected individuals who have poor hand hygiene, consumption of contaminated food or water, and contact with contaminated surfaces. Flies can also serve as mechanical vectors, especially in areas with inadequate sanitation. Children in daycare settings are at particularly high risk because they may not practice proper handwashing and often share toys and surfaces.

How Shigella damages the intestine 🔗

Once ingested, Shigella bacteria survive passage through the stomach acid-unlike many other pathogens-and multiply in the small intestine before reaching the colon. In the large intestine, the bacteria invade the epithelial cells lining the intestinal wall. This invasion triggers an intense inflammatory response characterized by hyperemia, edema, leukocytic infiltration, and superficial mucosal ulcerations.

The resulting damage to the intestinal lining causes the hallmark symptoms of dysentery: small-volume stools containing blood, mucus, pus, and bacteria. The inflammatory process also affects normal intestinal function, leading to abdominal cramping and tenesmus-the painful, persistent urge to defecate even when the rectum is empty.

Clinical presentation in children 🔗

Symptoms typically appear 1 to 4 days after exposure to the bacteria. The clinical picture can range from mild watery diarrhea to severe, life-threatening dysentery.

Common signs and symptoms 🔗

In young children, shigellosis often begins with sudden onset of high fever-commonly reaching 39.4°C to 40°C. This is accompanied by abdominal cramping, which occurs in 70% to 90% of cases. Diarrhea follows, initially watery but progressively becoming bloody with visible mucus. Other symptoms include nausea, vomiting, loss of appetite, and general malaise. Tenesmus is particularly distressing and involves frequent, painful straining with passage of small amounts of bloody mucoid stool.

In severe cases, children may develop signs of dehydration including dry mucous membranes, decreased skin turgor, sunken eyes, reduced urine output, and lethargy. Infants may present with a sunken fontanelle. High fever combined with dehydration can lead to seizures in young children.

Neurological manifestations 🔗

Seizures are a notable complication, occurring in approximately 5% to 10% of hospitalized children with shigellosis. According to the CDC, children who experience seizures during Shigella infection typically have high fever, low blood sugar, or electrolyte imbalances. These seizures are usually generalized and self-limiting. Encephalopathy with lethargy, confusion, and headache has been observed in up to 40% of hospitalized children with severe infections.

Diagnosis of shigellosis 🔗

Clinical suspicion should arise in any child presenting with bloody diarrhea, especially if there is a history of sick contacts or recent attendance at a childcare facility. However, definitive diagnosis requires laboratory confirmation.

Stool examination and culture 🔗

The gold standard for diagnosis is isolation of Shigella organisms from stool culture. Microscopic examination of fecal smears may reveal sheets of polymorphonuclear cells, indicating an inflammatory process. Stool samples should be collected and transported promptly, as Shigella is fragile and may not survive prolonged storage.

Rapid diagnostic tests using polymerase chain reaction (PCR) technology can detect Shigella DNA and provide faster results than traditional culture methods. Given the increasing prevalence of antimicrobial resistance, susceptibility testing is essential when planning antibiotic therapy.

Treatment approach 🔗

Management of bacillary dysentery focuses on three key pillars: rehydration, antibiotic therapy when indicated, and nutritional support.

Rehydration therapy 🔗

Replacing lost fluids and electrolytes is the cornerstone of treatment. For children with mild to moderate dehydration, oral rehydration solution (ORS) is the preferred approach. ORS contains a precise balance of glucose, sodium, and other electrolytes that facilitates absorption even when the intestinal lining is damaged.

Children with severe dehydration require intravenous fluid therapy. According to WHO guidelines, Ringer’s lactate solution or normal saline should be administered rapidly, with reassessment every 15 to 30 minutes until circulation improves. Once the child can drink, oral rehydration should be initiated alongside IV therapy.

Importantly, anti-diarrheal medications like loperamide are contraindicated in shigellosis. These agents can worsen symptoms and may predispose to toxic dilatation of the colon.

Antibiotic therapy 🔗

Unlike many causes of acute diarrhea, shigellosis generally warrants antibiotic treatment. Antibiotics reduce the duration and severity of illness and help limit transmission to others. However, antimicrobial resistance has become a significant challenge, with widespread resistance to traditional agents like ampicillin, trimethoprim-sulfamethoxazole, and tetracyclines.

Current first-line options include fluoroquinolones (such as ciprofloxacin), azithromycin, and third-generation cephalosporins (such as ceftriaxone). Selection should ideally be guided by local resistance patterns and, when available, individual susceptibility testing results. In children, ciprofloxacin at 15 mg/kg twice daily for 3 days is commonly recommended when susceptibility is unknown.

Nutritional support 🔗

Continued feeding during illness is essential for recovery. Breastfed infants should continue nursing even during the acute phase. For older children, a regular age-appropriate diet should be maintained, though temporarily avoiding lactose-containing products may help if lactose malabsorption develops. Clear liquids followed by a low-residue diet are recommended until symptoms resolve.

Potential complications 🔗

While most children recover within 5 to 7 days, serious complications can occur, particularly in malnourished or immunocompromised children.

Hemolytic uremic syndrome (HUS) is a rare but serious complication associated with Shiga toxin-producing strains, particularly S. dysenteriae type 1. HUS causes destruction of red blood cells, low platelet counts, and acute kidney injury. It typically develops about 7 days after symptom onset, when diarrhea is actually improving.

Rectal prolapse may occur in infants and young children due to severe inflammation of the rectum and distal colon combined with frequent straining.

Reactive arthritis can develop after infection, particularly with S. flexneri, causing joint pain, eye irritation, and painful urination. This complication is more common in individuals with the HLA-B27 genotype.

Bacteremia is uncommon but more likely in children under five years, those with severe malnutrition, or immunocompromised patients.

Prevention and infection control 🔗

Preventing the spread of shigellosis requires strict attention to hygiene and appropriate isolation measures.

Hand hygiene 🔗

Thorough handwashing with soap and water is the single most effective preventive measure. Hands should be washed after using the toilet, after changing diapers, and before preparing or eating food. Alcohol-based hand sanitizers are less effective against Shigella than soap and water.

Isolation precautions 🔗

Infected children should be kept away from childcare settings until they have been symptom-free for at least 24 hours. In healthcare settings, contact precautions are essential for children who cannot maintain hygiene independently. Soiled clothing and bedding should be handled carefully and washed in hot water with disinfectant.

Environmental measures 🔗

Contaminated surfaces should be cleaned and disinfected promptly. Food should be thoroughly cooked, and fruits and vegetables washed carefully before consumption. Access to safe drinking water is crucial in preventing waterborne transmission.

Key nursing considerations 🔗

Paediatric nurses play a vital role in managing children with shigellosis. Priority nursing interventions include careful assessment of hydration status using clinical indicators like skin turgor, mucous membrane moisture, and urine output. Accurate intake and output monitoring helps guide fluid replacement therapy.

Administering ORS requires patience and technique-small, frequent sips are more effective than large volumes, and a clean spoon or cup should be used rather than bottles. Nurses should monitor for signs of complications, including declining urine output (suggesting HUS), seizure activity, or altered consciousness.

Education for parents and caregivers is equally important. This includes proper hand hygiene techniques, safe food handling practices, recognition of dehydration signs, and the importance of completing the full course of prescribed antibiotics.

What do you think? How can healthcare facilities and daycare centres better implement infection control measures to prevent shigellosis outbreaks? What challenges have you encountered when educating parents about preventing the spread of gastrointestinal infections in children?

References

1. https://www.cdc.gov/shigella/about/index.html
2. https://www.ncbi.nlm.nih.gov/books/NBK482337/
3. https://www.pasteur.fr/en/medical-center/disease-sheets/shigellosis
4. https://medlineplus.gov/ency/article/000510.htm
5. https://www.merckmanuals.com/professional/infectious-diseases/gram-negative-bacilli/shigellosis
6. https://emedicine.medscape.com/article/182767-overview
7. https://www.cdc.gov/shigella/signs-symptoms/index.html
8. https://www.sciencedirect.com/topics/nursing-and-health-professions/oral-rehydration-therapy
9. https://www.ncbi.nlm.nih.gov/books/NBK154434/
10. https://emedicine.medscape.com/article/182767-treatment
11. https://www.cdc.gov/shigella/hcp/clinical-overview/index.html
12. https://www.niddk.nih.gov/health-information/kidney-disease/children/hemolytic-uremic-syndrome