THE BRIEF CASE
crossm Closing the Brief Case: Angiostrongylus cantonensis Eosinophilic Meningitis in a Returned Traveler Kunatum Prasidthrathsint,a Julia Lewis,b Marc Roger Couturiera,c
KEYWORDS Angiostrongylus, Hawaii, eosinophilic meningitis, parasitology, serology
ANSWERS TO SELF-ASSESSMENT QUESTIONS 1. Which of the following options is the most likely diagnosis for a returning traveler from Hawaii with a headache, a stiff neck, photophobia, fever, and a CSF profile of WBC at 270/l, RBC at 2/l, mononuclear cells at 85%, eosinophils at 12%, and PMN at 3%? A. B. C. D.
Citation Prasidthrathsint K, Lewis J, Couturier MR. 2017. Closing the Brief Case: Angiostrongylus cantonensis eosinophilic meningitis in a returned traveler. J Clin Microbiol 55:3147–3148. https://doi.org/10 .1128/JCM.02429-16. Editor Carey-Ann D. Burnham, Washington University School of Medicine
Leptospira spp. Angiostrongylus cantonensis Herpes simplex virus 2 Trichinella spiralis
Copyright © 2017 American Society for Microbiology. All Rights Reserved.
Answer: B. Despite the fact that eosinophils are not the predominant leukocytes, having eosinophils in the CSF is considered abnormal and is most consistent with Angiostrongylus cantonensis. The definition of eosinophilic meningitis is an eosinophil count of ⱖ10% of the total CSF leukocytes.
Address correspondence to Marc Roger Couturier, [email protected]. See page 2880 in this issue (https://doi.org/10 .1128/JCM.02427-16) for case presentation and discussion.
2. Which one of the following pathogens can also induce CSF eosinophilia? A. B. C. D.
Acanthamoeba Taenia saginata Baylisascaris procyonis Trichostrongylus
Answer: C. Baylisascaris procyonis causes eosinophilic meningitis and often results in long-lasting sequelae, such as brain damage and vision loss. Infections are often fatal. 3. Which of the following is well known to generate cross-reactive IgG antibodies to Taenia solium (cysticercosis) antigens? A. B. C. D.
Toxocara canis Entamoeba histolytica Echinococcus granulosus Endolimax nana
Answer: C. Echinococcus granulosus is known to generate cross-reactivity to Taenia solium IgG by ELISA, likely due to crude antigen extract used in the ELISA.
October 2017 Volume 55 Issue 10
Journal of Clinical Microbiology
jcm.asm.org 3147
Downloaded from http://jcm.asm.org/ on September 28, 2017 by guest
Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, USAa; Department of Internal Medicine, Infectious Disease, University of Utah School of Medicine, Salt Lake City, Utah, USAb; ARUP Laboratories, Salt Lake City, Utah, USAc
The Brief Case
Journal of Clinical Microbiology
TAKE-HOME POINTS ● Angiostrongylus cantonensis is endemic to several U.S. states and cannot be
considered only an exotic, travel-related parasite. ● Patients with eosinophilic meningitis who have traveled to or resided in regions
where Angiostrongylus cantonensis is endemic (regardless of a documented history of consumption of raw or undercooked intermediate or paratenic hosts) should always be tested for angiostrongyliasis. ● CSF eosinophilia is an invaluable marker for predicting angiostrongyliasis when
compatible epidemiological exposure is documented. ● In the United States, confirming the diagnosis of A. cantonensis eosinophilic
Downloaded from http://jcm.asm.org/ on September 28, 2017 by guest
meningitis requires CSF real-time PCR by the CDC. However, the diagnosis may require both real-time PCR and immunodiagnosis due to the transient presence of nematode DNA in the CSF during the course of the illness. ● The cross-reactivity between various parasites by ELISA methods is well docu-
mented. Caution should be exercised when interpreting IgG ELISA results, particularly for patients from areas where multiple parasitic helminths are endemic. Patients with little or no risk of a specific parasite should not be tested by IgG ELISA to avoid false-positive results.
October 2017 Volume 55 Issue 10
jcm.asm.org 3148
crossm Closing the Brief Case: Angiostrongylus cantonensis Eosinophilic Meningitis in a Returned Traveler Kunatum Prasidthrathsint,a Julia Lewis,b Marc Roger Couturiera,c
KEYWORDS Angiostrongylus, Hawaii, eosinophilic meningitis, parasitology, serology
ANSWERS TO SELF-ASSESSMENT QUESTIONS 1. Which of the following options is the most likely diagnosis for a returning traveler from Hawaii with a headache, a stiff neck, photophobia, fever, and a CSF profile of WBC at 270/l, RBC at 2/l, mononuclear cells at 85%, eosinophils at 12%, and PMN at 3%? A. B. C. D.
Citation Prasidthrathsint K, Lewis J, Couturier MR. 2017. Closing the Brief Case: Angiostrongylus cantonensis eosinophilic meningitis in a returned traveler. J Clin Microbiol 55:3147–3148. https://doi.org/10 .1128/JCM.02429-16. Editor Carey-Ann D. Burnham, Washington University School of Medicine
Leptospira spp. Angiostrongylus cantonensis Herpes simplex virus 2 Trichinella spiralis
Copyright © 2017 American Society for Microbiology. All Rights Reserved.
Answer: B. Despite the fact that eosinophils are not the predominant leukocytes, having eosinophils in the CSF is considered abnormal and is most consistent with Angiostrongylus cantonensis. The definition of eosinophilic meningitis is an eosinophil count of ⱖ10% of the total CSF leukocytes.
Address correspondence to Marc Roger Couturier, [email protected]. See page 2880 in this issue (https://doi.org/10 .1128/JCM.02427-16) for case presentation and discussion.
2. Which one of the following pathogens can also induce CSF eosinophilia? A. B. C. D.
Acanthamoeba Taenia saginata Baylisascaris procyonis Trichostrongylus
Answer: C. Baylisascaris procyonis causes eosinophilic meningitis and often results in long-lasting sequelae, such as brain damage and vision loss. Infections are often fatal. 3. Which of the following is well known to generate cross-reactive IgG antibodies to Taenia solium (cysticercosis) antigens? A. B. C. D.
Toxocara canis Entamoeba histolytica Echinococcus granulosus Endolimax nana
Answer: C. Echinococcus granulosus is known to generate cross-reactivity to Taenia solium IgG by ELISA, likely due to crude antigen extract used in the ELISA.
October 2017 Volume 55 Issue 10
Journal of Clinical Microbiology
jcm.asm.org 3147
Downloaded from http://jcm.asm.org/ on September 28, 2017 by guest
Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, USAa; Department of Internal Medicine, Infectious Disease, University of Utah School of Medicine, Salt Lake City, Utah, USAb; ARUP Laboratories, Salt Lake City, Utah, USAc
The Brief Case
Journal of Clinical Microbiology
TAKE-HOME POINTS ● Angiostrongylus cantonensis is endemic to several U.S. states and cannot be
considered only an exotic, travel-related parasite. ● Patients with eosinophilic meningitis who have traveled to or resided in regions
where Angiostrongylus cantonensis is endemic (regardless of a documented history of consumption of raw or undercooked intermediate or paratenic hosts) should always be tested for angiostrongyliasis. ● CSF eosinophilia is an invaluable marker for predicting angiostrongyliasis when
compatible epidemiological exposure is documented. ● In the United States, confirming the diagnosis of A. cantonensis eosinophilic
Downloaded from http://jcm.asm.org/ on September 28, 2017 by guest
meningitis requires CSF real-time PCR by the CDC. However, the diagnosis may require both real-time PCR and immunodiagnosis due to the transient presence of nematode DNA in the CSF during the course of the illness. ● The cross-reactivity between various parasites by ELISA methods is well docu-
mented. Caution should be exercised when interpreting IgG ELISA results, particularly for patients from areas where multiple parasitic helminths are endemic. Patients with little or no risk of a specific parasite should not be tested by IgG ELISA to avoid false-positive results.
October 2017 Volume 55 Issue 10
jcm.asm.org 3148
