Address for Correspondence:
Dr P.K Sasidharan
Professor of Medicine
Dept of Medicine
Calicut Medical College
Calicut -673008,Kerala,India
E-Mail: sasidharanpk@eth.net

Background: More than 200 persons developed Enteric fever after a marriage feast in April 1991 held at Calicut. I had the opportunity to identify the organism and to treat a good number of them personally during my private consultation. The houses of the married couple were near my residence and people started coming in large numbers starting from the third day of the feast. Enteric fever was considered as the first possibility and it was decided to study the manifestations by proper recording. A Performa was prepared and the details of each patient were entered. I have personally seen all the cases. After confirming the aetiology by blood culture and with the help of sensitivity report, Chloramphenicol was started as the primary drug , on an outpatient basis while many patients , who were hospitalised in different places were getting rathere expensive drugs like Ofloxacin and Ciprofloxacin. The total number of cases I could record went upto 71.


Materials and Methods
There were 71 cases (Males 46 , Females 25) whose age ranged from 6-60 years.

Criteria for inclusion: 1) Attendance at the marriage feast folowed by febrile illness, with constitutional symptoms like headache, body pain .2) Absence of any other obvious cause for the symptoms. 3) Blood or stool culture positivity . 4) Widal positivity. Those who fulfilled three out of four criteria were included in the study. 

Criteria for exclusion : Absence of symptoms suggestive of enteric fever on follow up. 2) Proof of having some other illness . 3). Widal and culture negativity.

A detailed history was taken followed by proper physical examination and the details were entered in Performa. TLC and DLC was done in all cases. Blood or stool culture was done if patients have not already received any antibiotic. Widal was done in all cases except 9 of them who were initially seen elsewhere and were responding to medical treatment. The investigations were all done from one particular lab where a qualified microbiologist supervised them. After starting treatment all the patients were followed up till they recovered from the illness.

Observations

Source of infection :

the source of infection was presumed to be from the marriage feast as only those who attended the marriage got the disease sparing other members who did not attend it. All of them got the disease between 3 to 45 days after the feast and there was clustering of cases. A total of 200 cases were reported from different hospitals in the region. Food items implicated were water or curd served in the feast. For technical reasons, isolation of organisms from the alleged food samples could not be effected. 
Incubation Period : 

The study gave an opportunity to find out the incubation period, since all the subjects presumably got the infecting dose on the same day, the day of development of symptoms thus corresponding to the incubation period. The details of incubation period are as follows.
 3 to 4 days - 6%
 5 to 8 days - 30 %
 9 to 12 days - 10%
 13 to 16 days -14%
 17 to 20 days - 11%
 21 to 24 days - 13%
 25 to 28 days - 4%
 29 to 32 days - 4%
 >33 days - 8%

Clinical Features
First symptom was headache in 44% of the patients studied. Fever and headache together were present as the initial symptoms in 21% of cases. Fever alone was the first symptom in 25% of cases. In the rest of the patients the initial t symptoms were 
Fever plus myalgia, Fever plus eye congestion, Lowback ache plus myalgia and myalgia & tiredeness

Nature of Fever :
 Low grade throughout -19(26%)
 High grade throughout -37(52%)
 Low grade initially and then becoming high-15(22%)
 Chills and rigor was present in 6 of them (8%).

Cough - was present in 38 patients (54%). All of them had dry cough only; in two of them it was severe enough to be mistaken for acute bronchitis, but they had persistent fever.
Loose stools - were present in 48 cases (67%). The colour of the stool was greenish black in 90% of these patients- fitting with the classical description of pea soup stool. One patient had frank blood &mucus, which was present in the first week of the illness ,typical of a bacillary dysentery. 

Increased gastrocolic reflex suggestive of mild colitis was present in 3 patients
Enteric facies was observed in 60 patients (84%). Myalgia in 40%, Low backacke in 3 patients and vomiting in 8% of cases. Meteorism or abdominal discomfort with dyspepsia were present in 21%, Dysuria in 11%, Arthralgia and Sorethroat in one patient each. 
Splenomegaly with a soft splenic tip was palpable in 42%.
Jaundice was present in 2 patients.

Initial Diagnosis
In spite of the high index of suspicion of enteric fever, initial clinical diagnosis was Enteric fever only in 58 patients. (82%). In others the following were the initial diagnoses:
 Viral fever -10(14%)
 UTI- One patient; who had dysuria high fever with chills and rigor and pus cells in urine, but subsequently the patient had other typical symptoms and signs and had positive Widal
 Sinusitis-One patient came with fever and unilateral headache with blocked nostril on that side, but the next day he came with high fever and had other symptoms to suggest enteric fever. The unilateral headache was due to coexisting allergic rhinitis.
 Bacillary dysentery- in one patient: who presented with typical blood and mucus , the stool culture isolated Salmonella Typhi.

Investigations
· TLC ranged from 4600- 12000/mm3 (Mean:6900)
· Relative lymphocytosis -10(14%).
· No cytopenia was obswervd .

Widal Test was done in 62 patients and positivity was considered when the titer was more than >1/60 . Positive titer ranged from 1/60 to 1/960.
 Antibodies to both O and H antigens were positive in 56 (80%).
 Antibody to H antigen alone was seen in 2 patients (3 %).
 Antibody to O antigen alone in 12 patients ( 17% ).
 Antibody to H antigen was more significantly raised than O antigen in - 16%
 Negative Widal was seen in 12(19%), but in 11 of them the test was done before 8th day. There was only one patient who had a negative Widal after 8 days of illness.

* Blood C/S could be arranged only in 25 Patients with isolation of Salmonella Typhi in 
15 of them. 

· Mean date of positive culture was 8 ± 3 days
· Stool C/S could be done in only 9 cases. Salmonella Typhi was isolated in 5 of them, the cultures being positive between 5th to 29th day of illness.

Antibiotic sensitivity pattern : In all cases the organisms were sensitive to Chloramphenicol, Ciprofloxacin and Cotrimoxazole

Treatment details: 58 cases were managed as outpatient and only 13 required hospitalization , that too because of severe constitutional symptoms, vomiting, coexisting jaundice or rigor and the initial confusion in diagnosis. Details of the drugs used are as follows:
 Chloramphenicol- in 40 cases (14days)
 Cotrimoxazole-in 12 (14days)
 Ciprofloxacin-in 10 (10days)
 Ofloxacin- in 2 (10days)
 Furazolidone - in 2 (14days)
 Spontaneous remission of symptoms were seen in 3 cases: They had only mild symptoms hence antibiotic was not started on first visit but Widal was positive and blood counts were suggestive.
 2 cases were lost to follow up. 

Response to treatment : All patients became afebrile in 2-7 days time (mean response time was 4days)

Side effects of drugs
Drug Side Effect No of cases Change of drug
Chloramphenicol Pruritic rash 2 Ciprofloxacin
Chloramphenicol Stomatitis/chelitis 2 Nil
Chloramphenicol Oral Ulcers/gum swelling 1 Nil
Ciprofloxacin Acute Colitis 1 Nil +Metronidazole
Cotrimoxazole Acute Colitis 1 Chloramphenicol

Relapses : 

There were 5 cases of relapse as given below:
 3/12 of Cotrimoxazole
 2/40 of Chloramphenicol
Cotrimoxazole relapses were treated with Chloramphenicol and Chloramphenicol relapses were treated with Ciprofloxacin. 

Special mention of a case : 
 A 23 year oldmale, vender of vegetable & fruits, had received chloramphenicol from elsewhere, but took the drug only for 8days and stopped the treatment when he became asymptomatic. His stool culture showed profuse growth of Salmonella Typhi. He actually came with another member of his house who also had gone for the marriage and developed enteric fever. 


Caution : 
 Malarial Parasite should be examined in those whom Malaria cannot be excluded
 Blood C/S should be done whenever possible
 Bone marrow C/S for Salmonella culture in difficult cases for diagnosis especially when there is no response to initial treatment.

Conclusions from the study
1. Water was the most likely source of infection as at least one person who got the disease took nothing except one glass of water from the place.
2. Shortest incubation period wasis 3 days
3. Maximum number of patients contracted the disease in 3 to 8 days
4. Headache was the first symptom in 50% or more cases .
5. Any pattern of fever is possible ,but chills were unusual
6. Pea soup stools was a common observation
7. Respiratory/GIT/Urinary symptoms can dominate in some patients and can create confusion in diagnosis
8. Relative lymphocytosis was unusual
9. Absence of neutrophilic leucocytosis was characteristic 
10. Blood C/S, stool C/S should be done whenever possible
11. Spontaneous remissions are possible
12. Chloramphenicol is a useful drug.
13. Relapses were more with cotrimoxazole
14. Advise about prevention of spread to each patient and family members is essential for prevention of the disease and complete treatment has to be ensured .
15. Tracing the source of infection is important in Prevention of the disease
16. Identifying high risk cases for transmission of the disease, like food handlers and elling them about the precautions to be adopted while handling food is very important. 
17. Hospitalisation is not essential in management of uncomplicated cases, especially in the first week.

Related Articles in This Issue:

Lathi N, Sudarsana J. Changing Sensitivity Pattern of Salmonella Typhi in Calicut
Calicut Medical Journal 2004;2(1):e2
URL: http://www.calicutmedicaljournal.org/2004/2/1/e2/index.html 

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