|
|
Letter
Human Metapneumovirus and
Chronic Obstructive Pulmonary Disease
Diego Vicente,*
Milagrosa Montes,* Gustavo Cilla,* and Emilio Pérez-Trallero*†
*Hospital Donostia, San Sebastián, Spain; and †Basque Country University,
San Sebastián, Spain
Suggested citation
for this article:
Vicente D, Montes M, Cilla G, Pérez-Trallero E. Human metapneumovirus
and chronic obstructive pulmonary disease [letter]. Emerg Infect Dis
[serial on the Internet] 2004 Jul [date cited]. Available from:
http://www.cdc.gov/ncidod/EID/vol10no7/03-0633.htm
To the Editor: We read with interest an article, Human Metapneumovirus
Detection in Patients with Severe Acute Respiratory Syndrome, in your
journal (1). In the report, Chan et al., did not question
that SARS-CoV is the etiologic agent of severe acute respiratory syndrome
(SARS); however, human metapneumovirus (HMPV) was found in 25 (52%) of
48 probable SARS cases that were investigated, and SARS-CoV was detected
in 11 (22.9%) of them. Another recent article reported HMPV in five of
six patients in whom SARS was diagnosed in Canada (2);
four of the six were coinfected with SARS-CoV. The prevalence of HMPV
infection in SARS patients validates the interest in HMPV’s possible role
in SARS etiology.
From November 2001 to February 2002, 1 year before the first cases of
SARS appeared, we tested the sputum of patients >64 years of age who
had experienced exacerbation of chronic obstructive pulmonary disease,
for HMPV. Investigations were conducted on 90 episodes in 89 elderly patients,
62 males and 27 females, in which we found no other microorganisms that
could have been related to the exacerbation of chronic obstructive pulmonary
disease. RNA was extracted from the sputum samples and amplified by reverse
transcriptase–polymerase chain reaction (RT-PCR) to detect HMPV as previously
described (3). Results of bacterial culture and culture
and PCR to detect respiratory syncytial virus and influenza virus types
A and B were negative, whereas HMPV was found in the sputum of five (three
men and two women) immunocompetent patients, 77–87 years of age. The prevalence
of HMPV infection was 5.5%, similar to the percentage obtained by Chan
et al., when HMPV RT-PCR was conducted on the respiratory samples. Fever
(temperature >38°C) was not present in any of the five patients
infected with HMPV. Two patients were admitted to a hospital. Both patients
had bronchial infection and cough with bronchospasm and moderate respiratory
insufficiency (oxygen saturation rate: 90.3% and 88%, respectively) for
>1 week. Sputum samples from an additional 70 elderly patients with
exacerbation of chronic obstructive pulmonary disease with positive detection
for influenza virus (n = 50) or respiratory syncytial virus (n = 20) were
tested for HMPV infection. None of the samples showed HMPV infection.
Sequence analysis of amplicons from the five samples positive for HMPV
infection showed >95% similarity with HMPV sequences found in other
parts of the world (4,5). Additional studies should be
conducted to confirm that HMPV exacerbates chronic obstructive pulmonary
disease. However, by performing an RT-PCR directly on the sample instead
of the more efficient RT-PCR after viral culture used by Chan et al.,
these findings suggest that HMPV is a frequently undetected agent in acute
respiratory infection unrelated to SARS. The important questions are whether
HMPV and SARS-CoV coinfection would facilitate more severe SARS, or whether
HMPV infection would facilitate a more efficient transmission of SARS-CoV.
References
- Chan PKS, Tam JS, Lam C-W, Chan E, Wu A, Li C-K, et
al. Human
metapneumovirus detection in patients with severe acute respiratory
syndrome. Emerg Infect Dis. 2003;9:1058–63.
- Poutanen SM, Low DE, Henry B, Finkelstein S, Rose D, Green K, et al.
Identification
of severe acute respiratory syndrome in Canada. N Engl J Med. 2003;348:1995–2003.
- Vicente D, Cilla G, Montes M, Pérez-Trallero E. Human
metapneumovirus and community-acquired respiratory illness in children.
Emerg Infect Dis. 2003;9:602–3.
- van den Hoogen BG, de Jong JC, Groen J, Kuiken T, de Groot R, Fouchier
RA, et al. A
newly discovered human pneumovirus isolated from young children with
respiratory tract disease. Nat Med. 2001;7:719–24.
- Peret TC, Boivin G, Li Y, Couillard M, Humphrey C, Osterhaus AD, et
al. Characterization
of human metapneumoviruses isolated from patients in North America.
J Infect Dis. 2002;185:1660–3.
|
