|
Viral
Influenza Associated Flareups of Fibrodysplasia Ossificans Progressiva
Richard
Scarlett, B.S., David Rocke, Ph.D., Sharon Kantanie, M.A.T., Jean
Patel, M.D., Eileen Shore, Ph.D., Frederick Kaplan, M.D.
Introduction:
In patients with fibrodysplasia ossificans progressiva (FOP),
flareups leading to heterotopic (extra) bone formation are most
commonly triggered by soft tissue injury. Viral illnesses have long
been suspected to trigger FOP flareups, but to date there has been
little evidence of a viral association. In January 2001, we observed
severe flareups leading to mobility restriction in two half-sisters
with FOP within 12 hours of the onset of symptoms of culture-confirmed
influenza B infection.
Methods:
In order to determine the potential association and impact of
influenza infections with flareups of FOP, a questionnaire was designed
to assess whether patients with FOP experienced influenza symptoms
during the 2000-2001 influenza season (October 2000 - April 2001),
and whether flareups of FOP were correlated with influenza infections.
The questionnaire was posted electronically on the International
Fibrodysplasia Ossificans Progressiva (IFOPA) website (www.ifopa.org)
and translated into relevant languages. All 264 members of the IFOPA
were requested to participate in the study. Postal questionnaires
were mailed to all IFOPA members worldwide who did not complete
the electronic version.
Results:
Of the 264 members (115 males, 149 females) in the IFOPA, there
were 123 respondents (53 males, 70 females), representing 47 percent
of the known FOP population worldwide. Using stringent clinical
criteria for viral influenza infection, 10 of the 123 respondents
(8 percent) had contracted influenza during the 2000-2001 flu season.
Of the ten patients reporting influenza infection, six (60 percent)
experienced flareups of FOP during the viral illness. Five of these
six developed heterotopic bone formation and permanent loss of mobility.
There was no difference in age between those who experienced flareups
and those who did not (mean age 28/29 years, respectively). Of the
113 patients who did not report symptoms consistent with influenza,
12 patients (11 percent) described disease flareups during the 2000-2001
influenza season. Of the 123 patients who responded to the survey,
28 reported receiving influenza immunization. Only one patient who
received the flu vaccine (prophylactic immunization) contracted
influenza. There were no reported episodes of heterotopic ossification
as a result of influenza immunization. However, two patients reported
experiencing flareups of FOP after receiving intramuscular influenza
vaccinations during prior influenza seasons.
Conclusion:
These data strongly suggest that influenza infections serve
as a trigger for disabling flareups in patients with FOP. FOP patients
who HAD influenza had a 60% chance of having a flareup AS A RESULT
OF THE INFLUENZA, while FOP patients who did not have influenza
had only an 11% chance of having a flareup during the flu season.
These data are highly statistically significant. Prophylactic immunization
against viral influenza may be a reasonably safe and effective means
of preventing this unique complication of influenza in the FOP patient
population. We recommend that patients with FOP, especially those
who are older and already have severe restrictive disease of the
chest wall, consider receiving non-intramuscular influenza immunizations
(subcutaneous administration). Since the vaccine is most often given
intramuscularly, you will need to make a special request for subcutaneous
vaccination. The flu vaccine should never be given to someone who
is allergic to eggs (since the flu vaccine is developed and cultured
with eggs).
Additionally,
unaffected household members of FOP patients should also be consider
being immunized annually. An intranasal spray preparation of the
influenza vaccine is currently undergoing evaluation by the U.S.
Food and Drug Administration (FDA). If and when the intranasal influenza
vaccine is approved, it would be the ideal route of administration
for patients with FOP. Anecdotal evidence from patients leads us
to recommend that influenza immunizations should not be administered
while a patient is experiencing a flareup.
The
lab would like to express our appreciation to the members of the
IFOPA who participated in this study. Without the data from these
families, we would not have been able to discover that a link between
FOP flareups and influenza infection exists.
Protecting
yourself against the flu:
Keep
your body as healthy as possible&emdash;good diet, sleep well
Avoid
people who you know are sick
Wash
hands frequently&emdash;and keep them away from your face and eyes,
minimizing the chance that the virus will be transmitted to the
bloodstream
Flu
Vaccine (Ask for subcutaneous injection because of the risk of intramuscular
injection for FOP)
If
the bug bites:
The Food and Drug Administration has approved two new drugs.
Relenza (zanamiver) is an inhaled prescription drug that can reduce
symptoms of Influenza A and B and speed recovery if taken within
the first two days of symptoms. Tamiflu (osteltamivir) is a pill
that produces similar results. Tamiflu has also been approved for
flu prevention (taking the drug to help prevent spread of flu virus),
and studies have also shown that Relenza may be helpful for flu
prevention as well.
Two
other prescription drugs, amantadine and rimantadine, can also help
reduce symptoms, but they only work against influenza A. And they
too must be taken within 48 hours, and drug resistance may develop.
In
the future, a nasal flu vaccine may also be available. Unlike injections,
this vaccine is inhaled. However, because this vaccine uses a "live"
flu virus, this past summer the Food and Drug Administration decided
that more studies are needed to determine its safety.
Treat
the family with the flu patient:
When flu strikes, treating other family members with antiviral
medications, not just the affected individual, seems to reduce the
risk of spreading the illness. In the study at Saint Louis University,
flu victims were treated with oseltamivir (Tamiflu) and their family
members were given either the drug or a placebo once a day for 10
days. Of the 406 family members who took the drug, 11 got the flu.
In the untreated group of 392 people, 40 came down with the flu.
The findings were recently presented at the American Society for
Microbiology meeting in Chicago.
Learn
more about influenza by visiting:
http://www.msnbc.com/news/INFECTIOUS_front.asp
|
