PG DISSERTATION SYNOPSIS
CLINICAL PROFILE OF RICKETTSIAL INFECTION
1 .Name of the candidate and Address : Dr. Kurian Thomas
Residential address : Koilparambil House
Arpookara East. P. O
Kottayam
Kerala
2. Name of the institution : St. John’s Medical College,
Bangalore - 560034
3. Course of the study and subject : M.D (General Medicine)
4. Date of admission : 16th April 2011
5. Title of the topic :
“CLINICAL PROFILE OF RICKETTSIAL INFECTION”
6. BRIEF RESUME OF THE INTENDED WORK
6.1 NEED FOR THE STUDY
The incidence of rickettsial infection had seen a significant decline in the nineties secondary to widespread use of insecticides. But the past decade has again witnessed a resurgence in the incidence of rickettsial infection.
Though varieties of rickettsial infections are described in literature the main agent that we come across is rickettsial typhus caused by Orientia tsutsugamushi. In most clinical scenarios the presentation of rickettsial infection refuses to fit into a particular pattern. The clinical presentation of rickettsial infection is wide and varied and the severity also varies from mild to severe
Today rickettsial infection can be accurately diagnosed by immunofluresence and ELISA. But these tests are very expensive and are not easily available. As a result the main diagnostic tool in the clinicians hand is still the weil-felix test. Weil felix test has less sensitivity but the specificity has been proven to be quite acceptable.
In view of this it is imperative that the wide and varied clinical presentations of rickettsial infections be studied in detail because if intervened at an appropriate stage rickettsial infection has excellent prognosis
6.2 REVIEW OF LITERATURE
Rickettsial infection is endemic in the tropical and sub tropical regions of the Asian continent. The main agent causing rickettsial infection in our country is Orientia tsutsugamushi,which is the etiological agent for scrub typhus.[1] Multiple studies conducted in India and abroad have validated the re-emerging trend of rickettsial infection.[1,2,3,4]
The clinical presentation of rickettsial infection is varied and refuses to fit into a particular pattern. Various clinical conditions where the diagnosis of rickettsial infection should be considered are fever without source, pyrexia of unknown origin (PUO), fever with rash (rash which is petechial, involving palms and soles, having centripetal spread), fever with eschar, meningoencephalitis or aseptic meningitis, acute renal insufficiency with eschar, and infective vasculitides.[5]
The clinical features of rickettsial infection in general include fever with chills and rigour (100%), vomiting (43%), headache and myalgias (38%), lymphadenopathy (53%), jaundice (53%), congested eyes (34%), hepato-splenomegaly (43%), pain abdomen (29%), diarrhea (18%)[6], dyspnea (18%)[6], altered sensorium (24%), seizures (19%), abnormal bleeding (14%), rash (10%) and eschar (10%).[3] Rickettsial infection can lead onto serious end organ which includes pneumonitis, ARDS, acute renal failure, myocarditis, disseminated intravascular coagulation (DIC)[7] and septic shock.[6]
Doxycycline is the drug of choice for most rickettsial infections.[8] With early intervention, extremely favourable response is seen. No significant morbidity or mortality has been reported in patients who receive early and appropriate treatment.[7]
The gold standard test for the diagnosis of rickettsial infection is immunofluorescent assay. However, as it is highly expensive and not freely available in India, it is seldom used. Also there is little consensus apparent in the choice of IFA methodology (i.e., antigenic strains and antibody isotype) and of the positivity cutoff limits for diagnostic purposes. Hence in an endemic country like India, the seroprevalence in the normal population has to be estimated before IFA can be used as a diagnostic method.[9]
Weil – felix test is still the widely used test for diagnosis of rickettsial infection. Even though the sensitivity of the weil – felix test is low, it has high specificity and positive predictive value. In a study by Isaac R et al, it was shown that the sensitivity for Ox-K was 30% at a titre breakpoint of 1:80, but the specificity and positive predictive value were 100%. At a breakpoint of 1:20, the sensitivity was 61%, the specificity was 94%, and positive predictive value was 84%. At a breakpoint of 1:40, the sensitivity was 49%, the specificity was 96%, and positive predictive value was 88%.[1]
Considering the endemicity of rickettsial infection in our country and the inexpensive yet effective treatment options available, it is highly unlikely that the weil – felix test will be replaced anytime soon by an expensive investigation such as the IFA. Hence it is imperative that the clinical profile of rickettsial infection be studied in detail so as to assist the clinician in making an early diagnosis.
6.3 AIMS AND OBJECTIVES
1. To assess the clinical profile of rickettsial infection
2. To assess organ dysfunction in rickettsial infection with special focus on renal manifestations
7. MATERIALS AND METHODS
7.1 SOURCE OF DATA
Place of Study : St. John’s Medical College Hospital, Bangalore
Study period : 1st August 2012 to 31st October 2013
Method : Descriptive study design
Sample size : 75
INCLUSION CRITERIA
1. Weil felix positivity in dilutions greater than 1 in 160
2. Typical clinical presentations with eschar
EXCLUSION CRITERIA
1. Subjects who do not consent for the study.
2. Subjects less than 18 years of age
3. Cases with other established causes of infection
7.2 METHOD OF COLLECTION OF DATA
Cases of fever admitted in the study period in our hospital will be followed up on the basis of weil felix positivity. The clinical presentation and multiple organ dysfunction in these patients will be evaluated with special focus on the renal manifestations. In possible cases a paired serology will be done to further validate the diagnosis of rickettsial infection. Cases in which a more sensitive investigation such as blood or urine culture comes positive will be excluded even if there is a high probability of rickettsial disease coexisting so as to prevent dilution of data. The renal manifestations in normal patients and those with baseline renal impairment will be studied and compared in detail. The treatment protocol adopted and the response to treatment will also be scrutinised
CLINICAL ASSESSMENT PROFORMA
Name:
MRD No:
Age: IP No:
Sex:
Residence :
Occupation :
Similar ailment in relatives :
Co morbidities if any :
Yes / No /History of tick bite :
Clinical features
Yes / No /Fever
Yes / No /Chills and Rigor
Yes / No /Yes / No /
Malaise
Myalgia
Yes / No /Rash
Yes / No /Eschar
Yes / No /Headache
Yes / No /Giddiness
Yes / No /Altered sensorium
Yes / No /Seizures
Yes / No /Cough
Yes / No /Sore throat
Yes / No /Difficulty in breathing
Yes / No /Chest pain
Yes / No /Palpitation
Yes / No /Nausea
Yes / No /Vomiting
Yes / No /Diarrhoea
Yes / No /Abdominal pain
Yes / No /Oliguria / Decreased urine output
Yes / No /Facial puffiness
Yes / No /Congestion of eyes
Yes / No /Pedal edema
Yes / No /Any bleeding manifestations
Vitals at admission
a. Pulse
b. Blood pressure
c. Respiratory rate
d. Temperature
General examination
Yes / No /Pallor
Yes / No /Yes / No /
Icterus
Yes / No /Cyanosis
Clubbing
Yes / No /Lymphadenopathy
Yes / No /Edema
Yes / No /Elevated JVP
Yes / No /Rash
Extent of rash (if present):
Yes / No /Eschar
Any other notable findings:
Systemic findings
a. Respiratory
b. Cardiovascular
c. Gastrointestinal
d. Nervous system
Provisional diagnosis :
Vitals at admission
a. Pulse
b. Blood pressure
c. Respiratory rate
d. Temperature
General examination
Yes / No /Pallor
Yes / No /Yes / No /
Icterus
Yes / No /Cyanosis
Clubbing
Yes / No /Lymphadenopathy
Yes / No /Edema
Yes / No /Elevated JVP
Yes / No /Rash
Extent of rash (if present):
Yes / No /Eschar
Any other notable findings:
Systemic findings
a. Respiratory
b. Cardiovascular
c. Gastrointestinal
d. Nervous system
Provisional diagnosis :
Laboratory investigations
Weil felix titre :
ü Hb :
ü Leukocyte count :
P / L / Eü Differential count
ü Platelet count :
ü ESR :
ü Blood urea :
ü Serum creatinine :
ü Serum electrolytes
a. S. Na+ :
b. S. K+ :
ü Liver function test
a. AST :
b. ALT :
c. ALP :
ü Routine urine :
ü Specific fever workup for infection –
Yes / No /a. MP
Yes / No /b. Dengue
Yes / No /c. Leptospirosis
Yes / No /d. Widal
Yes / No /e. Blood culture
Yes / No /f. Urine culture
g. Others
ü Chest x-ray
ü ECG
ü Ultrasound abdomen
Treatment
Choice of antibiotic :
Details
Other significant management:
Renal dysfunction
Yes / No /History of renal dysfunction
Yes / No /Renal dysfunction
Oliguric / Non oliguric /If yes,
Yes / No /Haematuria
Macroscopic / af / Microscopic / aYes / No /
Proteinuria
Baseline serum creatinine (if available):
Serum creatinine at admission :
Dialysis
Yes / No /Is dialysis required
No of times dialyzed :
Response to treatment :
Yes / No /Renal scan
Renal function at the time of discharge
8. LIST OF REFERENCES
1. Isaac R, Verghese GM, Mathai E et al, Scrub typhus : prevalence and diagnostic issues in rural southern india, Clinical Infectious diseases, 2004 Nov, vol 39, pp. 1395 – 1396
2. Mathai E., Rolain JM, Verghese GM et al, Outbreak of scrub typhus in southern India during the cooler months, Annals of the New York Academy of Sciences, June 2003, Vol 990, pp. 359 – 364. Available from www.pubmed.com (PMID 12860654)
3. SK Mahajan, R Kashyap, A Kanga,V Sharma, BS Prasher, LS Pal, Relevance of Weil-Felix test in the diagnosis of scrub typhus in India, Journal of The Association of Physicians of India, Aug 2006, Vol 54, pp. 619 – 621
4. Paddock CD, The science and fiction of emerging rickettsioses, Annals of the New York Academy of Sciences, May 2009, Vol 1166, pp.133 – 143
5. Narendra Rathi, Akanksha Rathi, Rickettsial infections : Indian perspective, Indian Paediatrics, Feb 17 2010, vol 47, pp.157 - 164
6. Tsay RW, Chang F Y, Serious complications in scrub typhus, Journal of Microbiology, Immunology and Infection, 1998, vol 31(4), pp. 240 - 244
- Mohd Ashraf, Arshad Farooq, Saika Bashia et al, Renal failure association with scrub typhus, JK Science, 2010 april-june, vol 12 (2), Available from http://jkscience.org/archive/volume122/Renal%20Failure%20Associated%20with%20Scrub%20Typhus11.pdf
8. David H. Walker, J. Stephen Dumler, Thomas Marrie. Harrison’s Principles of Internal Medicine 18th edition. McGraw-Hill Companies Inc.; 2012. Chapter 174 The Rickettsial Diseases. pp.1407 – 1417
9. Stuart D Blacksell, Naomi J Bryant, Daniel H Paris et al, Scrub typhus serological testing with the indirect immunofluorescence method as diagnostic gold standard: A lack of consensus leads to a lot of confusion, Clinical Infectious Diseases, 2007, vol 44, pp.391-401
9. SIGNATURE OF CANDIDATE :
10. REMARKS OF THE GUIDE :
11. NAME AND DESIGNATION OF
11.1 Guide : DR. SEENA SANKAR
ASSOCIATE PROFESSOR
DEPT. OF GENERAL MEDICINE
11.2 Signature :
11.3 Co-guide : DR. PRASHANTH G KEDALYA
ASSOCIATE PROFESSOR
DEPT. OF NEPHROLOGY
11.4 Signature :
11.5 Head of Department : DR. G D RAVEENDRAN
PROFESSOR & HOD
DEPT. OF GENERAL MEDICINE
11.6 Signature :
12.1. REMARKS OF PRINCIPAL:
12.2. Signature :