Atypical presentation of Salmonella Typhi infection
Dear Editor,
Enteric fever is caused by Salmonella Typhi. It is endemic in developing countries like India . It
also causes localized infection in immunocompromised patients but localization to skin
presenting as skin ulcer occurs very rarely.
We report a case of 50 year old male came with complaints of pain and swelling over left ankle
region followed by ulcer since 2 weeks. On examination a single oval shaped ulcer of size 1x2
cm present over lateral malleolous of left ankle region with shallow edges. The discharge was
collected on lateral pressure and sent for culture sensitivity.Bacteriological examination showed
growth of non lactose fermenting colonies on MacConkey agar(Hi-Media) which was identified
as Salmonella typhi
by using necessary biochemical reactions.Serotyping with specific
polyvalent(poly 0),monovalent(09) antisera confirmed the diagnosis.The bacteria was sensitive
to ciprofloxacin,ceftriaxone,cotrimaxazole,Amikacin resistant to Nalidixic acid,chloramphenicol
and ampicillin.
Salmonellae are gram negative, nonsporing ,motile bacteria belonging to Enterobacteriaceae
family.The genus
subspecies
of
Salmonella includes 2 species S.enterica and S.bongori.There are six
S.enterica,the
most
important
of
which
is
S.enterica
subspecies
enterica(subspecies1) which includes the typhoid bacilli.Members of the other five subspecies
(ii-vi) are in the main parasites of cold blooded animals or are found in the natural
environment.The subspecies are divided into serotypes basing on their somatic(O) and
flagellar(H) antigens and till now more than 2000 serotypes are known .These serotypes are
grouped into A-D basing on the common O antigen of which Salmonella typhi is included in the
group D.(1)The infection is usually initiated by ingestion of sufficient organisms to colonize the
gut and express the mechanisms resulting in clinical disease.Once it attaches to the host intestinal
mucosa there will be degeneration of microvilli through which salmonella enters the intestinal
epithelial cells.Some bacteria may penetrate into the submucosa and pass to the local mesenteric
lymphnodes.After ileal penetration the symptoms of diarrhea begins.For strains of Salmonella
typhi infection involves the invasion of the blood stream and various organs.(2)
Although it can cause a wide spectrum of clinical illness there are four major syndromes namely
entericfever, gastroenteritis, bacteraemia with or without metastatic infection and the
symptomatic carrier state.Transient bacteraemia occurs in 4% of cases of enteric fever due to
Salmonella typhi but in most cases the organisms are cleared from the blood. It can be isolated
from the blood in about 90% of patients during the first week and from 50% of patients at the
end of third week.It may also be isolated from faeces and urine through out the illness.
But in rare cases dissemination to different sites of body where pre existing abnormality is seen
in tissue or organ causing localized infection commonly seen in immunocompromised
patients.But localization to skin presenting as skin ulcer occurs very rarely.But in our case the
cutaneous ulceration is the only manifestation of infection in an immunocompetant
individual.Source of the infection cannot be traced out.He is a agricultural field worker by
profession,so the source of infection could have been material contaminated with Salmonella
typhi or infection by trauma induced skin lesion. Only few cases of skin manifestations caused
by Salmonella typhi have been reported.(3)It rarely causes soft tissue infections at the sites of
local trauma(4). Localised infection due to it have been described in bones &joints,
intraperitoneal, splenic, breast and subcutaneous regions(5).The patient was treated with
ciprofloxacin 500mg BD for 15 days with complete cure.Cultures performed after healing failed
to grow any organism.To conclude in endemic countries like India the atypical presentations due
to Salmonella Typhi should be kept in mind so that there is no delay in treating the patient.
REFERENCES:
1. Old DC,Threl fall EJ. Salmonella.In :Balows A,Duerden BI eds.Topley and Wilson’s
Microbiology&Microbial infections.1998;969-997.
2. Green Wood D,Slack RCB,Peutherer JF eds.Chart H,Salmonella.In :Medical Microbiology
2008;250-259.
3. Thakur K,Singh G,Gupta P,Chauhan S,Jaryal SC.Primary anterior parietal wall abscess due to
Salmonella Typhi. Braz J InfectDis 2010; 14(4):328-329.
4.Raghunath R,Ashok AC,Sridaran D,Indumathi VA,Belwadi MR.Acase of injection abscess
due to Salmonella Typhi.Indian J Med Microbiol 2003;21:59-60.
5. Marzano AV ,Mercogliano M, Borghi A, Facchetti M,Caputo R.Cutaneous infection caused
by Salmonella Typhi.European Academy of Dermatology and VenereologyJEADV (2003)
17,575-77.