Meningitis: Eosinophilic Postneurosurgical Steroids in Acute Bacterial Meningitis

1. Meningitis:Eosinophilic Postneurosurgical Steroids in Acute Bacterial Meningitis

2. You are consulted on this 33 yo male returning from Thailand with peripheral blood and CSF eosinophilia, HA, neck stiffness, and paresthesias across his chest and face…

3. Nematodes Angiostrongylus cantonensis Gnathostoma spinigerum Baylisascaris procyonis Toxocara canis Cestodes Taenia solium Trematodes Paragonimus westermani Schistosomiasis Fascioliasis Eosinophilic Meningitis Ectopic CNS

4. Nonparasitic Coccidiomycosis Cryptococcosis Myiasis Noninfectious Foreign material in CNS Idiopathic hypereosinophilic syndrome Leukemia/lymphoma Cipro/Bactrim Intraventricular gentamicin/vanc NSAIDS Myelography contrast Eosinophilic Meningitis

6. Adults reside in pulmonary arteries of rats Eggs hatch in the lungs, the larvae are swallowed, expelled in feces and seek an appropriate molluscan intermediate host Develops into infective larvae in: Slugs, land snails Freshwater prawns, land and coconut crabs, frogs Angiostrongylus cantonensis

7. Coconut Crabs

8. Humans are incidental hosts Larvae migrate to brain and die

9. Angiostrongylus cantonensis • Epidemics and sporadic infections reported in • South Pacific • Southeast Asia • Tawain • Jamaica, Cuba, Egypt • Recognized sources of human infection • Raw or undercooked snails, prawns, crabs • Contamination of leafy vegetables by larvae deposited by slugs or snails • Caesar salad recognized in one epidemic

11. NEJM 2002 246:668

13. 12 cases • 9 hospitalized • Median #days until HA – 11 days (6-31) • CSF eosinophilia in 5/9 patients • Peripheral blood eosinophilia in 9/9 however only 4/9 at admission • 3 pts with severe HA requiring repeat LPs and steroids

14. All patients ate Caesar salad in Jamaica on April 8 • Romaine lettuce was imported from U.S. • Canned, salted anchovies • Unknown if Jamaican parsley garnish present

15. Figure 1. Adult Angiostrongyluscantonensis recovered from rat lungs. A. Adult female worm with characteristic barber-pole appearance (anterior end of worm is to the top). Scale bar = 1 mm. B. Tail of adult male, showing copulatory bursa and long spicules (arrows). Scale bar = 85 µm.

17. Infection in New Orleans • 11 yo boy • Children’s Hospital June 1993 • 7 days of HA, myalgias • 5 days of low-grade fever and stiff neck • WBC 10.6 N51L36E6 • CSF WBC 215 68% lymphs 16% eos • Admitted to eating a raw snail off the street after a dare

18. Angiostrongylus infection • Disease self-limited • Rare fatal cases (massive inoculum) • Incubation period 1-6 days after ingestion of infected snails • HA, stiff neck, fever, rash, pruritus, abdominal pain, nausea, vomiting • Paresthesias – chest wall, face, limbs • Cranial nerve palsies (fourth and sixth most common)

19. Angiostrongylus infection • Occasionally larva seen on CSF • MRI may show meningeal enhancement or tracts in the brain, subcortical lesions • Heavy worm burden increases probability of brain involvement • Serology to 31 kD Angiostrongylus cantonensis antigen

20. Angiostrongylus treatment • Supportive care • Killing larvae in and around the brain may be detrimental • Repeated lumbar punctures helpful in treating headaches • Recovery usually complete by 2 months • Corticosteroids decrease duration of headaches CID 2000; 31: 660-2

24. Steroids in Angiostrongylus infection • Prednisone 60 mg po qd for 2 weeks decreases duration of headache from 13 days to 5 days • No data on mortality or using steroids in large worm burden patients but this makes pathophysiologic sense

25. You are consulted on a 20 yo traveler returning from Korea (after eating the pickled fish and kimchi) with high peripheral eosinophilia and eosinophilic meningitis…

26. Gnathostoma spinigerum • Adult worms reside in stomachs of cats, dogs, opposums, raccoons • Eggs shed in feces and hatch in one week • Subsequently ingested by small crustaceans called Cyclops • These crustaceans are then ingested by fishes, frogs, snakes where they encyst in the muscle as infectious larvae

27. Gnathostoma spinigerum • Most infections occur after eating undercooked or pickled freshwater fish, chicken or pork • Infectious larvae can also burrow through the skin • Infections may occur after ingesting Cyclops in contaminated water Kimchi preparation Cyclops

28. Gnathostomiasis • Nausea, vomiting, gastrointestinal pain and fever shortly after ingestion • 3-4 weeks after ingestion, intermittent migratory subcutaneous swellings • Usually nonpitting, often erythematous, and occasionally pruritic and painful • May resemble classic cutaneous larva migrans • Eosinophilia may be extreme

29. Gnathostomiasis • Migrating larvae may invade any tissue • Although gnathostomiasis is a less frequent cause of encephalomyelitis compared to A. cantonensis it tends to result in permanent neurologic deficits and death because there is more invasion of the brain • Ivermectin and albendazole give cure rates >90%

31. You are consulted on a 32 yo man who cleaned raccoon feces off of his house then rubbed his eye…

33. Baylisascaris procyonis • Ascarid of raccoons • Visceral larval migrans in humans • Severe and commonly fatal eosinophilic meningoencephalitis occurs in more than half the cases • Eye involvement is common • Diagnosed by detecting larvae in tissue • Experimental serology • Albendazole and steroids are commonly tried

34. “Raccoon Roundworm” Encephalitis LATIN Procyon lotor • Pro – before • Kyon – dog • Lotor -- washer Procyon lotor

37. CID 2004: 39 (15 November) p 1484

38. Risk Factors for Baylisascariasis • Exposure to raccoon latrines • PICA/geophagia • Age < 4 yrs • Male sex

39. Asymptomatic infections? • 389 children in Chicago • Ages 1-4 yrs • 8% seropositive for Baylisascaris procyonis • Previously, only 2 cases of severe CNS baylisascariasis in children in Chicago suburbs Pediatr Infect Dis J. 2002 Oct;21(10):971-5.

40. Bayliscariasis • Once shed in raccoon feces, the Baylisascaris procyonis eggs become infective in 2-4 weeks • After ingestion of eggs, infective larvae emerge, penetrate gut and migrate through liver and lung and are distributed by bloodstream to somatic tissues • Only 5-7% of ingested larvae penetrate CNS and eye

41. Bayliscariasis • Severity of disease • Number of eggs ingested • Extent/location of larval migration • Severity of ensuing inflammation and necrosis

42. Diagnosis • Clinical findings and exposure • Stool O&P on patient not useful (no adult in intestines) • Peripheral and CNS eosinophilia • Deep white matter lesions on MRI • Serology • Dept of Veterinary Pathology at Purdue • (765) 494-7558 • Exclusion of other causes of visceral, ocular or neural larval migrans • ELISA for Toxocara at CDC

43. Treatment • Laser photocoagulation in ocular dz • No cure for clinical disease • Albendazole and dexamethasone used with good CNS and ocular penetration • Prophylaxis with albendazole on days 1-10 or days 3-10 after exposure offers 95-100% protection • No children receiving albendazole after eating raccoon feces have developed baylisascariasis CID 2004: 39 (15 November)

44. Toxocara canis • Rarely visceral larval migrans of toxocariasis can involve the CNS • Several case reports of albendazole and corticosteroids with good outcome • Definitive diagnosis by demonstration of larvae in tissue • ELISA serology Am J Trop Med Hyg. 2003 Sep;69(3):341-3.

45. Board Review