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Year : 2004  |  Volume : 22  |  Issue : 3  |  Page : 191--192

Meningitis due to aeromonas hydrophila

KS Seetha, BT Jose, A Jasthi 
 Department of Microbiology, Kasturba Medical College Hospital, Manipal - 576 104, Karnataka, India

Correspondence Address:
K S Seetha
Department of Microbiology, Kasturba Medical College Hospital, Manipal - 576 104, Karnataka


A 3-month-old male child with the history of fever, of not sucking the breast and exhibiting\symptoms of meningitis was brought to the hospital for medical advice and was investigated. Aeromonas hydrophila was isolated thrice from CSF, blood samples as well as the water source.

How to cite this article:
Seetha K S, Jose B T, Jasthi A. Meningitis due to aeromonas hydrophila.Indian J Med Microbiol 2004;22:191-192

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Seetha K S, Jose B T, Jasthi A. Meningitis due to aeromonas hydrophila. Indian J Med Microbiol [serial online] 2004 [cited 2020 Feb 28 ];22:191-192
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Full Text

Members of the genus Aeromonas are gram negative, catalase and oxidase positive facultative anaerobic bacilli that have been associated with a wide range of illnesses in humans, including gastrointestinal disorders and systemic infections in both immunocompromised and healthy host.[1]

The family Aeromonadaceae includes over 14 species in the genus Aeromonas[2] with only 6 species being currently recognized as human pathogens. The bacteria are distributed worldwide in the primary habitats that are surface water and soil. Geographical differences in the distribution of the genospecies are evident with human infections in temperate regions occurring predominantly in summer because of the aquatic nature of the organisms and the seasonal prevalence.

Majority of the serious infections caused by this organism occur in individuals with certain predisposing conditions; the most relevant example being that of Aeromonas septicaemia. Individuals with hepatic disorders, malignancies and biliary obstruction are at greater risk in contracting septicaemia although it can occur in patients with no apparent immunological and physiological deficits.[3] The incidence of septicaemia, however, is relatively low, accounting for less than 0.15% cases.

Meningitis caused by this organism is a rare clinical entity. Aeromonas meningitis may involve all age groups and can be either community or nosocomially acquired.[4],[5] The species may be attributed with the acquisition of certain pathogenic determinants that confer it with greater invasive capabilities.[4]

 Case Report

A 3-month-old male child with the history of fever, of not sucking the breast and deviation of eyeball towards the right side was brought to the hospital for medical advice and was investigated.

On examination, the patient was conscious, irritable, with no eye contact, did not recognize the mother, had no social smile, was continuously crying, seizures were under control and his pulse and BP were normal. Routine haematological examination showed a WBC count of 16,600 cells/cumm and Hb of 8.9 gm%. Urine examination showed occasional WBC and protein. His cardiovascular and respiratory system examination were unremarkable.

The biochemical analysis of CSF revealed concentration of glucose and protein as 14 mg/dL and 198 mg/dL respectively. The cytological analysis showed a total WBC count of 770 cells/cumm (N-75%, L-25%) and the total RBC count of 50 cells/cumm.

Microbiological Investigation

The CSF sample was subjected to Gram stain which revealed plenty of pus cells and gram negative bacilli. CSF cultures were done by standard techniques.[6]

The identification was established by growth of haemolytic colonies on blood agar, lactose fermenting colonies on MacConkey agar and biochemical reactions. The biochemical profile was as follows: organism was catalase and oxidase positive, fermented almost all sugars, indole was produced, esculin was hydrolysed, lysine was decarboxylated, arginine was dihydrolysed and Voges Prausker test was positive.

The same organism was isolated from three CSF samples as well as from blood sample and well water of the patient's dwelling.


Aeromonas are motile gram negative bacilli, which are widely distributed in nature and are found in soil and most natural water systems as well as in domestic sinks, swimming pools and chlorinated hospital water in warm weather.

The spectrum of Aeromonas infections in humans is quite vast with the reports of associated acute gastroenteritis, liver abscess,[7],[8] meningitis,[9] osteomyelitis, endocarditis and myonecrosis.[10] Aeromonas bacteraemia is most commonly seen in children and adults[7],[9] and has often been due to Aeromonas hydrophila. Most patients have an underlying illness however even healthy patients can acquire bacteraemial infections due to Aeromonas species.

In spite of increasing reports of extra intestinal infections caused by Aeromonas spp., Aeromonas meningitis is an uncommon clinical entity and accounts for less than 0.15% of Aeromonas septicaemia. We isolated Aeromonas hydrophila from repeated CSF samples as well as from blood samples and the well water of their dwelling. A definite bacteraemia is defined as either two or more positive blood cultures or a single blood culture with an associated positive culture from the site of lesion.

Our patient was treated with injection ampicillin 250 mg I.V 6 hourly, injection gentamicin 12 mg I.V 12 hourly, injection fortum 250 mg I.V 12 hourly, immediately after admission. After repeated isolation from CSF and blood and persistence of gram negative bacilli and low grade fever I.V meropenem 100 mg 8 hourly and I.V cefipime 200 mg 12 hourly was added. Child became afebrile after 2 days and no further spikes of fever occurred till discharge.

CSF analysis done after 21 days of admission was normal and the child was put on oral ciprofloxacin and discharged.


1Janda JM, Duffy PS. Mesophilic Aeromonads in human disease: Current taxonomy, laboratory identification and infectious disease spectrum. Rev Infect Dis 1988;10:980-997.
2Carnahan AM, Behram S, Joseph SW. Aerokey II: A flexible key for identifying clinical Aeromonas species. J Clin Microbiol 1991;29:2843-2849.
3Janda JM, Guthertz LS, Kokka RP, Shimada T. Aeromonas species in septicemia: laboratory characteristics and clinical observations. Clin Infect Dis 1994;19:77-83.
4Parras F, Diaz MD, Reina J, Moreno S, Guerrero C, Bouza E. Meningitis due to Aeromonas spp: Case report and review. Clin Infect Dis 1993;17:1058-1060.
5Jacob L, Carron DB, Haji TC, Roberts DW. An unusual case of pyogenic meningitis due to Aeromonas sobria. Br J Hosp Med 1988;39:449.
6Collee JG, Fraser AG, Marmion BP, Simmons A. (Eds). Mackie and Mc Cartney Practical Medical Microbiology, 14th ed. (Churchill Livingstone, Edinburgh) 1996:77-83.
7Kannan S, Nair GB. Aeromonas: An emerging Pathogen associated with clinical spectrum and potential determinants of pathogenicity. Indian J Med Microbiol 2000;18(3):92-97.
8Kratzke RA, Golenbock DT. Pyomyositis and hepatic abscess in association with Aeromonas hydrophila sepsis. Am J Med 1987;83:347-349.
9Ellison RT III, Mostow SR. Pyogenic meningitis manifesting during therapy fort Aeromonas hydrophila sepsis. Arch Intern Med 1984;144:2078-2079.
10Heckerling PS, Stine TM, Pottege JC Jr, Levin S, Harris AA. Aeromonas hydrophila myonecrosis and gas gangrene in a immunocompromised host. Arch Intern Med 1983;143:2005-2007.