What are the systemic manifestations of worm infestations and how are they managed?

Systemic Manifestations of Worm Infestations and Their Management

Worm infestations can cause significant systemic manifestations beyond gastrointestinal symptoms, requiring specific diagnostic and treatment approaches based on the causative parasite. 1

Common Systemic Manifestations

• Eosinophilia: Elevated eosinophil count is a common finding in many helminth infections, particularly during tissue migration phases 1

• Loeffler's syndrome: Pulmonary manifestation characterized by transient pulmonary infiltrates and eosinophilia, commonly seen in ascariasis and strongyloidiasis 1

• Katayama syndrome: Acute schistosomiasis presenting with fever, urticaria, hepatosplenomegaly, and eosinophilia 1

• Larva currens: Rapidly moving, serpiginous, urticarial rash caused by migrating Strongyloides larvae 1

• Anemia: Particularly common in hookworm infections due to chronic blood loss, can be severe in elderly patients 2

• Neurological manifestations: Most severe with neurocysticercosis (T. solium) requiring specific treatment protocols 1

• Hepatosplenic disease: Chronic schistosomiasis can lead to hepatosplenomegaly, fibrosis, and portal hypertension 1

Diagnostic Approach by Parasite Type

Intestinal Nematodes

• Strongyloidiasis: Serology (most sensitive), concentrated stool microscopy, stool culture, or PCR 1
• Ascariasis: Concentrated stool microscopy or fecal PCR; may present with Loeffler's syndrome during migration phase 1
• Hookworm: Concentrated stool microscopy or fecal PCR; may present with iron-deficiency anemia 1, 2
• Pinworm: Cellophane tape test (sellotape test) performed in the morning before bathing; stool examination has poor sensitivity 3, 4

Cestodes (Tapeworms)

• Taenia species: Concentrated stool microscopy for ova or proglottids; cysticercosis serology for T. solium 1
• Hymenolepis: Concentrated stool microscopy or fecal PCR 1

Trematodes

• Schistosomiasis: Serology (positive at 4-8 weeks), concentrated stool samples, abdominal ultrasound 1

Treatment Protocols

Strongyloidiasis

• Standard infection: Ivermectin 200 μg/kg as a single dose 1, 5
• Hyperinfection syndrome: Requires urgent treatment and monitoring; may need repeated dosing 1
• Follow-up: At least three stool examinations over three months to ensure eradication 5

Ascariasis

• Treatment: Albendazole 400 mg or mebendazole 500 mg or ivermectin 200 μg/kg as a single dose 1
• Management of complications: Consider surgical intervention for intestinal obstruction 1

Hookworm

• Treatment: Albendazole 400 mg daily for 3 days 1
• Anemia management: Iron supplementation often required 2
• Severe disease: Consider prednisolone 40-60 mg once daily 1

Tapeworm Infections

• T. solium: Niclosamide 2 g single dose (only kills adult worms); praziquantel should be avoided unless neurocysticercosis has been excluded 1
• T. saginata: Praziquantel 10 mg/kg as a single dose 1
• Hymenolepis: Praziquantel 25 mg/kg as a single dose 1

Schistosomiasis

• S. mansoni, S. intercalatum, S. guineensis: Praziquantel 40 mg/kg as a single dose 1
• S. japonicum, S. mekongi: Praziquantel 60 mg/kg in two divided doses 1

Pinworm

• Treatment: Albendazole 400 mg or mebendazole 100 mg as a single dose, repeated after 2 weeks 3, 6
• Household management: Treat all household members simultaneously to prevent reinfection 6

Special Considerations

• Immunocompromised patients: At high risk for hyperinfection syndrome with strongyloidiasis; require aggressive treatment 1

• Pregnancy: Pyrantel pamoate preferred over mebendazole and albendazole for pinworm treatment 6

• Children: Major target for deworming programs due to higher worm burden and impact on development 7, 8

• Coinfections: Worm-infected individuals respond less well to vaccinations and may be more susceptible to other infections like HIV 9

Prevention Strategies

• Personal hygiene: Frequent handwashing, especially after bowel movements and before meals 6

• Environmental measures: Improved sanitation and access to clean water 7

• Mass deworming: Recommended in endemic areas with prevalence >40% (treat once yearly), >60% (treat twice yearly), or >80% (treat three times yearly) 8

• Follow-up: Regular screening in endemic areas to prevent reinfection and chronic complications 9