title: Clinical deterioration in community acquired infections associated with lymphocyte upsurge in immunocompetent hosts.
abstract: Clinical deterioration during the course of community-acquired infections can occur as a result of an exaggerated immune response of the host towards the inciting pathogens, leading to immune-mediated tissue damage. Whether a surge in the peripheral lymphocyte count can be used as a surrogate marker indicating the onset of immunopathological tissue damage is not known. In this study, we report the clinical presentations and outcomes of a cohort of immunocompetent patients with non-tuberculous community acquired infections who experienced clinical deterioration during hospital stay (n=85). 12 (14.1%) patients had a surge in lymphocyte count preceding their clinical deteriorations, and their diagnoses included viral pneumonitis , viral encephalitis , scrub typhus , leptospirosis , brucellosis , and dengue haemorrhagic fever . The clinical manifestations during deterioration ranged from interstitial pneumonitis , airway obstruction , CNS disturbances , and systemic capillary leak syndrome , all of which were thought to represent immunopathological tissue damages. When compared with patients without lymphocyte surge, these patients were more likely to be infected with fastidious/viral pathogens (0 vs 12; p<0.05), in addition to having lower mean baseline lymphocyte counts (403+/-181 vs 1143+/-686 cells/microl; p<0.05). We postulate that the peripheral lymphocyte count may be a useful surrogate marker indicating the presence of immunopathological damage during clinical deterioration in certain infectious diseases.
authors.affiliation: Division of Infectious Diseases, Centre of Infection Queen Mary Hospital, The University of Hong Kong, Hong Kong Special Administrative Region, China.
authors.forename: Vincent C C
authors.initials: VC
authors.lastname: Cheng
authors.forename: Alan K L
authors.initials: AK
authors.lastname: Wu
authors.forename: Ivan F N
authors.initials: IF
authors.lastname: Hung
authors.forename: Bone S F
authors.initials: BS
authors.lastname: Tang
authors.forename: Rodney A
authors.initials: RA
authors.lastname: Lee
authors.forename: Susanna K P
authors.initials: SK
authors.lastname: Lau
authors.forename: Patrick C Y
authors.initials: PC
authors.lastname: Woo
authors.forename: Kwok-Yung
authors.initials: KY
authors.lastname: Yuen
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents; D001424:Bacterial Infections / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000453:epidemiology / Q000382:microbiology* / Q000503:physiopathology*; D018450:Disease Progression; D004359:Drug Therapy, Combination / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization; D006801:Humans; D007121:Immunocompetence; D015994:Incidence; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011336:Probability; D011446:Prospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents