Laboratory-Acquired Serogroup A Meningococcal Meningitis

							 J Occup Health 2007; 49: 399–401


Case Study                                                         (CSF) showed 14,000 white blood cells (95%
                                                                   polymorphonuclear leukocytes) and 367 red blood cells/
L a b o r a t o r y - A c q u i r e d S e r o g ro u p A           mm3. Cerebrospinal fluid (CSF) protein was 265 mg/dl
                                                                   and the glucose level was 4 mg/dl. Gram stain, culture
Meningococcal Meningitis                                           and bacterial antigen testing of CSF were negative as
                                                                   were blood cultures, all taken reportedly before initiation
Alexander Tkeshelashvili KESSLER, David S. STEPHENS and
                                                                   of antibiotics.
Jyoti SOMANI
                                                                      The patient was started on antibiotic coverage for
Division of Infectious Diseases, Department of Medicine,           bacterial meningitis with ceftriaxone and vancomycin and
Emory University School of Medicine, USA                           required external ventricular drain placement for
                                                                   intracranial pressure reduction. On hospital day two,
Key words: Meningitis, Meningococcus, Serogroup A,                 meningococcal polymerase chain reaction (PCR)
Laboratory-acquired                                                performed on the initial CSF by the Centers for Disease
                                                                   Control and Prevention (CDC) was reactive for N.
  Neisseria meningitidis causes fulminant meningitis and           meningitidis serogroup A. During the hospitalization,
sepsis. Worldwide, N. meningitidis serogroup A is                  the patient reported plating N. meningitidis serogroup A
responsible for large epidemic outbreaks (e.g., sub-               in the research laboratory and admitted that this was not
Saharan Africa) and serogroups B, C, Y and W-135 cause             conducted under a biosafety cabinet. He also then denied
epidemic and endemic disease1–3). Meningococci are                 previous vaccination with meningococcal vaccine. He
usually transmitted from person to person through close            completed a 10-d course of antibiotics with intravenous
contact with contaminated aerosols and secretions from             penicillin, and rifampin was given to eradicate
the human nasopharynx. Laboratory-acquired infection               nasopharyngeal colonization; he had a full recovery.
has been reported infrequently but laboratory technicians          Significant contacts were traced and given
are at increased risk4–6). Most of the reported cases of           chemoprophylaxis, and there were no secondary cases.
laboratory-acquired infections occur in clinical
                                                                   Discussion
microbiology laboratories and have been due to
serogroups B and C. For reasons that are unclear, the                 Laboratory-acquired meningococcal disease is
reported mortality of laboratory-acquired N. meningitidis          infrequent but the risk appears to be underappreciated6).
sepsis or meningitis is ~50%4, 5), which is higher than            A case of laboratory-acquired meningococcal infection
mortality from endemic infections.                                 is defined as meningococcal disease in a laboratory
  We present the first reported case of laboratory-                worker who had laboratory exposure to a N. meningitidis
acquired serogroup A N. meningitidis meningitis in a 21            isolate within 14 d before the onset of illness and who
yr-old research laboratory assistant.                              has illness with the serogroup that matches the source
                                                                   isolate4–6). We report the first recent case of laboratory
Case Report                                                        acquired serogroup A meningococcal disease infection.
   A 21-yr old previously healthy student presented to             Boutet et al. in Great Britain demonstrated that laboratory
the emergency room with a 5-d history of progressively             workers exposed to N. meningitidis are at significantly
worsening headache, fever, vomiting and confusion. He              higher risk of developing infection than the general
lived in a student dormitory and was working in a                  population4). Recently, these data were expanded5, 6). A
meningococcal research laboratory for the summer.                  total of 16 cases were described in the literature since
Patient initially had reported to his physician and to his         1985, with six cases reported in the United States5). Nine
laboratory supervisor that he had been previously                  of the 16 cases were caused by serogroup B and seven
vaccinated against meningococcus. He denied taking any             by serogroup C. Individuals with laboratory-acquired
medications including antibiotics prior to his presentation.       meningococcal disease had performed the following
Upon admission to the hospital he was lethargic and                procedures: organism identification and reading of plates
febrile to 39.2°C. Physical examination was remarkable             (50%), subculturing (50%), and performing serogroup
for abnormal mental status and severe nuchal rigidity. A           determination (38%)5). Eight cases (50%) were fatal and
lumbar puncture revealed significantly elevated opening            in 15 of 16 reported cases, these procedures were not
pressure (over 30 cm of H2O) and cloudy cerebrospinal              performed within a level 2 biosafety cabinet. A median
fluid. Laboratory analysis of the cerebrospinal fluid              number of 4 d (range 2–10 d) occurred between handling
                                                                   the isolate and symptom onset. Source isolates were from
Received Sep 28, 2006; Accepted May 16, 2007                       blood or CSF with carriage isolates potentially less
Correspondence to: A. T. Kessler, Northside Medical Specialists,   pathogenic5). Currently, N. meninigitidis is considered a
15 Reinhardt College Parkway, Canton, GA 30117, USA (e-mail:       biosafety level-II organism and CDC guidelines
sandrok@pol.net)                                                   recommend using a biosafety cabinet when manipulating
 400                                                                                            J Occup Health, Vol. 49, 2007


samples that have a high potential for droplet or aerosol        MIC>0.25 mg/dl successfully identified based on PCR19).
production such as centrifuging, grinding and blending           Unfortunately, meningococcal PCR is not yet routinely
procedures and for activities involving production of            available in many clinical laboratories.
quantities or concentrations5, 7). Both microbiology and            Different serogroups of N. meningitidis have different
research laboratory workers handling meningococcal isolates      epidemic potential, public health importance, and
should strongly consider vaccination with the quadrivalent       geographic distribution. Most meningococcal infections
meningococcal vaccine or quadrivalent meningococcal              in the United Stated are currently caused by serogroups
conjugate vaccine which includes serogroup A, C, Y and           B, C and Y, with serogroup A meningococcal disease
W-135 capsular polysaccharides5–8). Antibodies generated         being extremely rare since the end of World War II. From
from vaccines, as opposed to conjugate vaccines, are             1977 to 1981 serogroup A infections represented 4.7%
usually not persistent, meningococcal polysaccharide             of all the meningococcal infections in the United States2).
therefore, revaccination should be considered 3–5 yr after       More recent surveillance data from 1992–1996 identified
receipt of the initial dose of meningococcal                     only two unconfirmed cases of serogroup A
polysaccharide vaccine in persons with ongoing                   meningococcal disease 3) . The reasons for the
meningococcal exposure6, 18). Meningococcal PCR has              disappearance of serogroup A disease in the United States
significant value in diagnosing meningococcal infections,        are not clear, but disappearance of disease has been
serogroup determination and penicillin susceptibility and        accompanied by the disappearance of serogroup A
should be developed for clinical laboratories.                   nasopharyngeal carriage. Epidemics of serogroup A
   The length of protection of the recently released             meningococcal disease continue to occur in other parts
quadrivalent meningococcal conjugate vaccine is                  of the world. Serogroup A outbreaks have occurred in
unknown but it has immunologic features predicting               association with the religious pilgrimages to Mecca in
longer protection: induction of immunologic memory,              1987 and 1992 with subsequent serogroup A outbreaks
higher antibody avidity and herd immunity. It is likely          in Sudan, Chad, Ethiopia, and other parts of sub-Saharan
this vaccine will replace the polysaccharide vaccine for         Africa1). Sporadic serogroup A meningococcal disease
prevention of laboratory-associated disease8).                   associated with these outbreaks also occurred in France
   The definitive diagnosis of meningococcal infection has       and Sweden but no cases were reported in the United
relied on the isolation of N. meningitidis from a sterile        States. However, the potential for serogroup A
body fluid. However, the sensitivity of routine diagnostic       meningococcal epidemic disease merits aggressive
studies such as Gram stain and culture is limited. In a          eradication of potential carriers.
study from Norway, Gram stain and culture from blood                Laboratory-acquired meningococcal infection is
and/or CSF yielded meningococci in only 62% of patients          associated with a case fatality rate of 50%4, 5). This may
with clinically suspected meningococcal disease 9) .             reflect the small number of cases, underreporting of mild
Previous administration of parenteral antibiotic therapy or      cases, exposure to highly virulent strains and/or high
inadequate collection/handling of the samples are possible       concentration of organisms encountered in the laboratory
reasons for the low sensitivity of the Gram stain and culture.   setting5). It was recently estimated that the attack rate of
Latex agglutination has been found to be less sensitive          meningococcal disease among microbiologists in U.S.
(61%) than Gram stain in diagnosing meningococcal                laboratories between 1996 and 2001 was 13/100,000,
meningitis; further, it is associated with a significant         compared to 0.2/100,000 among U.S. adults in general6).
number of false positive results (up to 54%)10).                 Laboratory workers handling meningococcal isolates
   The first report of meningococcal meningitis diagnosed        should be vaccinated with the quadrivalent meningococcal
by PCR in a patient with a culture-negative CSF was              vaccine and should conduct procedures with this organism
reported by Kristensen in 1991 11). Currently several            under a certified biosafety class II containment cabinet20).
oligonucleotides primer targets are being used for the           Alternative methods of respiratory protection, such as
detection and serogrouping of meningococci (NM1, NM2,            splash guards and masks require additional assessment5).
IS1106, ctrA, sia(syn)D, crgA), with excellent sensitivity       If a biosafety cabinet or other means of protection are not
(89–96.7%) and specificity (91–100%)12–17). In Great             available, manipulation of these isolates should be
Britain the development of a national PCR-based service          minimized and workers should consider sending specimens
increased the number of laboratory confirmed cases of            to laboratories that are appropriately equipped5). Exposure
meningococcal disease by 35%18). In addition, PCR is             to isolates of N. meningitidis, rather than patient samples,
useful in meningococcal serogroup determination4, 11).           increases the risk of infection. Education of microbiologists
Real-time PCR may further enhance PCR sensitivity in             and strict adherence to these safety guidelines would be
diagnosing meningococcal disease15, 17). Finally, PCR has        emphasized.
also been used for detection of penicillin resistance in N.         If a laboratory worker has a percutaneous exposure to
meningitidis with five out of 12 isolates with penicillin        an invasive N. meningitidis isolate from a sterile site, he
MIC of 0.2–0.25 mg/dl and all nine isolates with                 or she should receive treatment with penicillin; if there
 Alexander Tkeshelashvili KESSLER, et al.: Laboratory Aquisition of Meningococcal Meningitis                                  401


is a known mucosal exposure they should also received                       4th ed. Atlanta: U.S. Department of Health and Human
chemoprophylaxis5). If a microbiologist has manipulated                     Services, Centers for Disease Control and Prevention
invasive isolates in a manner that could result in                          and National Institutes of Health. 1999.
aerosolization and/or droplet formation (such as plating,              8)   Bilukha OO, Rosenstein N, National Center for
subculturing and serogrouping) in an open bench top in                      Infectious Diseases, Centers for Disease Control and
                                                                            Prevention: Prevention and control of meningococcal
the absence of respiratory protection, he or she should
                                                                            disease. Recommendations of the Advisory Committee
also consider appropriate antimicrobial prophylaxis5).                      on Immunization Practices (ACIP). MMWR Recomm
   In summary, we present a case of lab-acquired                            Rep 54, 1–21 (2005)
serogroup A meningococcal meningitis infection which                   9)   Gedde-Dahl TW, Hoiby EA, Schillinger A, Lystad A
was diagnosed by PCR, and which occurred in a student                       and Bovre K: An epidemiological, clinical and
working for the summer in a research laboratory. Our                        microbiological follow-up study of incident
case illustrates the value of meningococcal PCR in                          meningococcal disease cases in Norway, winter 1981–
diagnosing meningococcal infections, serogroup                              1982. Material and epidemiology in the MenOPP
determination and penicillin susceptibility and should be                   Project. Nat Instit Pub Health Annals (Oslo) 2, 155–
available for clinical laboratories. Our case is a reminder                 169 (1983)
that employees who will be handling highly infectious                10)    Perkins MD, Mirrett S and Reller LB: Rapid bacterial
                                                                            antigen detection is not clinically useful. J Clin
or toxic materials undergo mandatory training in
                                                                            Microbiol 33, 1486–1491 (1995)
occupational safety measures, and if available, be offered           11)    Kristensensen BE, Ask E, Jenkins A, Fermer C,
preventative immunization. This is as important for                         Radstrom P and Skold O: Rapid diagnosis of
temporary employees as it is for permanent ones and                         meningococcal meningitis by polymerase chain
should not be overlooked by Supervisors and by                              reaction. Lancet 337, 1568–1569 (1991)
Institutional occupational health and safety offices.                12)    Ni H, Knight AI, Cartwright K, Palmer WH and
   Acknowledgments: The authors would like to thank                         McFadden J: Polymerase chain reaction for diagnosis
Anne Whitney, PhD at Laboratory of Epidemic                                 of meningococcal Meningitis. Lancet 340, 1432–1434
Investigations, Meningitis and Special Pathogens Branch                     (1992)
at the CDC for her assistance and to Nancy Rosenstein,               13)    Porritt R, Mercer J and Munro R: Detection and
MD for helpful comments.                                                    serogroup determination of Neisseria meningitidis in
                                                                            CSF by polymerase Chain reaction. Pathology 32, 42–
References                                                                  45 (2000)
                                                                     14)    Taha M: Simultaneous approach for nonculture PCR-
 1) Rosenstein NE, Perkins BA, Stephens DS, Popovic T
                                                                            based identification and serogroup prediction on
    and Hughes JM: Meningococcal disease. N Engl J Med
                                                                            Neisseria Meningitidis. J Clin Microbiol 38, 855 (2000)
    344, 1378–1388 (2001)
                                                                     15)    Wood AL and Gill MJ: PCR and the investigation
 2) Schlech WF, Ward JI, Hightower A, Fraser DW and
                                                                            minfection of Meningococcal Infection. Epidemiol
    Broome CV: Bacterial meningitis in the United States,
                                                                            Infect 127, 269–274 (2001)
    1978 through 1981. The National Bacterial Meningitis
                                                                     16)    Saunders NB, Shoemaker DR, Brandt BL and Zollinger
    Surveillance Study. JAMA 253, 1749–1754 (1985)
                                                                            WD: Confirmation of suspicious cases of
 3) Rosenstein NE, Perkins BA, Stephens DS, Lefkowitz
                                                                            meningococcal meningitis by PCR and enzyme-linked
    L, Cartter ML, Danila R, Cieslak P, Shutt KA, Popovic
                                                                            immunosorbent assayAssay. J Clin Microbiol 35,
    T, Schuchat A, Harrision LH and Reingold AL: The
                                                                            3215–3219 (1997)
    changing epidemiology of meningococcal disease in
                                                                     17)    Hackett SJ, Carrol ED, Guiver M, Marsh J, Sills JA,
    the United States, 1992–1996. J Infect Dis 180, 1894–
                                                                            Thompson AP, Kaczmarski EB and Hart CA: Improved
    1901 (1999)
                                                                            case confirmation in meningococcal disease with whole
 4) Boutet R, Stuart JM, Kaczmaski EB, Gray SJ, Jones
                                                                            blood Taqman PCR. Arch Dis Child 86, 449–452
    DM and Andrews N: Risk of laboratory-acquired
                                                                            (2002)
    meningococcal disease. J Hosp Infect 49, 282–284
                                                                     18)    Kaczmarski EB, Ragunathan PL, Marsh J, Gray SJ and
    (2001)
                                                                            Guiver M: Creating a national service for the diagnosis
 5) Morbidity and Mortality Weekly Report (MMWR):
                                                                            of meningococcal disease by polymerase chain
    From the centers for disease control and prevention.
                                                                            reaction. Comm Dis Public Health 1, 54–56 (1998)
    Laboratory acquired meningococcal disease—United
                                                                     19     Maggs A, Logan J and Carter P: The detection of
    States, 2000. JAMA 287, 1256–1258 (2002)
                                                                            penicillin insensitivity in Neisseria meningitidis by
 6) Sejvar JJ, Johnson D, Popovic T, Miller JM, Downes
                                                                            polymerase chain reaction. J Antimicrob Chemother
    F, Somssel P, Weyant R, Shephens DS, Perkins BA
                                                                            42, 303–307 (1998)
    and Rosenstein NE. Assessing the risk of laboratory-
                                                                     20)    Centers for Disease Control and Prevention: Prevention
    acquired meningococcal disease. J Clin Microbiol 43,
                                                                            and Control of Meningococcal Disease.
    4811–4814 (2005)
                                                                            Recommendations of the Advisory Committee on
 7) Jonathan Y, Richmond ED, eds. Biosafety in
                                                                            Immunization Practices (ACIP). MMWR Morb Mortal
    Microbiological and Biomedical Laboratories (BMBL),
                                                                            Wkly Rep 49, 1–10 (2000)