1975. Clinicopathologic Characteristics and Immunolocalization of Viral Antigens in Chikungunya-Associated Fatal Cases Puerto Rico, 2014
Session: Oral Abstract Session: The Spectrum of Viral Infection
Saturday, October 10, 2015: 2:45 PM
Room: 32--ABC
Background: Death in patients with chikungunya is rare (<0.1% of clinical cases) and typically occurs in association with the extremes of age and/or co-morbidities. We describe the epidemiology and histopathologic findings for people that died and had evidence of chikungunya virus (CHIKV) infection during an outbreak in Puerto Rico.

Methods: We identified patients who died in 2014 following an acute febrile illness and had CHIKV RNA detected by RT-PCR in a pre- or post-mortem serum or tissue specimen. Immunohistochemical staining for CHIKV antigen was performed on tissue specimens. Data from medical records, autopsy findings, family interviews, and diagnostic test results were compiled.

Results: In total, 28 laboratory-positive CHIKV-associated fatal cases were identified (0.8 per 100,000 population). All cases were positive for CHIKV infection and negative for DENV infection by RT-PCR in blood and/or tissue specimens. Median age was 59 years (range: 6 days–85 years), and 17 (61%) were male. Median day of death post-illness onset was 6 (range: 1–21). Ten (36%) individuals died at home, and 7 (25%) had not sought medical care. Nearly all (93%) individuals had ≥1 co-morbidity, most frequently hypertension (54%), diabetes (39%), and obesity (39%). Five cases had only one recognized co-morbidity: one of each of the above, and one each with lupus and asthma. Nine case-patients had severe co-morbidities (e.g., chronic liver or kidney disease, sickle cell anemia) and/or co-infections (e.g., leptospirosis, nosocomial) that may have predisposed them to fatal outcome. Of 23 cases with available tissue specimens, 11 (48%) were positive by IHC. CHIKV antigen was detected in multiple organs, predominantly in mesenchymal tissues and cells of the mononuclear phagocytic system. Common histopathologic findings in tissue from IHC-positive cases included intraalveolar hemorrhage and edema.

Conclusion: Evaluation of autopsy tissue from patients infected with CHIKV provides evidence on the pathologic consequences of the disease that cannot be gained by blood-based diagnostic testing alone. This underscores the importance of enhanced surveillance, autopsies, and tissue-based diagnostic testing in understanding mortality associated with an emerging infectious disease.

Tyler Sharp, PhD1, Wun-Ju Shieh, MD, MPH, PhD2, Rebecca Levine, PhD2, Dianna M. Blau, DVM, PhD3, Jose Torres, MD4, Aidsa Rivera, MS5, Janice Perez-Padilla, RN, MPH6, Dana Thomas, MD, MPH7, Julio Cadiz Velazquez, MD, MPH7, Julu Bhatnagar, PhD2, Dianna Ng, MD2, M. Kelly Keating, MD2, Elizabeth Hunsperger, PhD5, Jorge L. Munoz-Jordan, PhD5, Dario Sanabria, MD4, Brenda Rivera Garcia, DVM, MPH7, Harold Margolis, MD, FIDSA6 and Sherif R. Zaki, MD, PhD3, (1)Dengue Branch, Division of Vector-Borne Diseases, Centers for Disease Control and Prevention (CDC), San Juan, PR, (2)Centers for Disease Control and Prevention, Atlanta, GA, (3)Infectious Disease Pathology Branch, Centers for Disease Control and Prevention, Atlanta, GA, (4)Instituto de Ciencias Forenses de Puerto Rico, San Juan, PR, (5)Dengue Branch, Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, San Juan, Puerto Rico, San Juan, PR, (6)Dengue Branch, Centers for Disease Control and Prevention, San Juan, PR, (7)Puerto Rico Department of Health, San Juan, PR

Disclosures:

T. Sharp, None

W. J. Shieh, None

R. Levine, None

D. M. Blau, None

J. Torres, None

A. Rivera, None

J. Perez-Padilla, None

D. Thomas, None

J. Cadiz Velazquez, None

J. Bhatnagar, None

D. Ng, None

M. K. Keating, None

E. Hunsperger, None

J. L. Munoz-Jordan, None

D. Sanabria, None

B. Rivera Garcia, None

H. Margolis, None

S. R. Zaki, None

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