“Better to light one candle than to curse the darkness.” An old adage. And the first quote in Carl Sagan’s “The Demon-Haunted World.” So, in the spirit of that adage, I’ll not bitch about the religious pollution here in India just now and instead I will share a summary paper on what I’ve done over the past five weeks. This is one little candle. Oh, and I believe in scientific openness – every new research should be disseminated online and through media to as wide an extent as possible.
The formatting got all messed up when I copied and pasted it from Word, so the original file is attached below. Oh wait, I can’t figure out how the fuck to attach a file, so nevermind.
Oh, and it’s missing an abstract and a personal statement. Don’t judge!
~Isaac
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Isaac Hanson
VCRC
Britto, Das, Yuvaraj
14 Dec 2007
ASO Levels and Frequency of Acute Bacterial Infection in Patients with Filarial Lymphedema
Introduction Lymphatic filariasis affects about 120 million people worldwide, including 15.5 million in India alone who suffer from chronic disease and 30 million asymptomatic carriers (Joseph et al. 2004; Wijesinghe et al. 2007). Filariasis manifests itself in several conditions, ranging from chronic carriers of parasites to those afflicted with the chronic form of the disease (Nandha et al. 2007). In addition to permanent swelling of the limbs, scrotum and sometimes breasts, chronic sufferers also endure periodic attacks of adenolymphangitis (ADL) (Pani and Das 2006). This acute attack can include severe symptoms of infection in the affected area and may resemble febrile septicemia elsewhere in the body (Suma et al. 1997). Chronic lymphedema combined with recurrent acute ADL attacks bring about significant physical, psychosocial and economic disability among many sufferers of filariasis (Wijesinghe et al. 2007).
The etiology of acute ADL attacks was poorly understood for some time until it became clear over the past decade that bacterial infection plays a significant role in the onset of ADL (Suma et al.2002; Jamal et al. 1990). Now that bacterial dermal flora is implicated, a possible new avenue of research is to identify how such bacteria lead to infection and possibly to predict ADL attacks.
The antistreptolysin O test measures the presence of antibodies to group A streptococcal antigens. As a result it serves as an indicator of recent infection with group A streptococci, which are normal inhabitants of the skin (Gerber et al. 1990). Suma at al. (1997) demonstrated that 90% of patients with filariasis-related ADL had a persistently elevated ASO titer. And Joseph et al. (2004) found that filarial lymphedema patients’ ASO titers were elevated during 84% of the ADL attacks recorded during their study. The present research seeks to evaluate the possible prognostic value of the ASO test by correlating the ASO titer to such measures as the patient’s grade of lymphedema and the frequency of past ADL attacks. The ASO titer may be useful in estimating a patient’s susceptibility to infection with acute ADL.
Materials and Methods Three groups of patients were studied: those with mild to moderate filarial lymphedema; those with more severe filarial lymphedema; and a control group consisting of persons who live in an area endemic for bancroftian filariasis but who have no history of filarial infection. The control group included one non-endemic control who resides outside the endemic area. Persons in the first two groups were residents of Pondicherry, southern India, and the surrounding region, an area endemic for bancroftian filariasis (Nandha et al. 2007). All patients were evaluated in the Filariasis Clinic of Vector Control Research Center, Pondicherry; and in the National Vector Borne Disease Control Programme (NVBDCP), Pondicherry; and in Chennagunam village in Tamil Nadu, on the outskirts of the city. Each patient was evaluated by a clinical doctor or a trained technician. Informed consent was obtained from each patient and they received standard medications for filariasis as well as multivitamins. The study protocol was submitted to the secretary of the institutional ethics committee for approval.
Patients were selected based on established history of filarial lymphedema, and most of them were regular patients of the VCRC or NVBDCP clinics. Patients over the age of 70 and minors were excluded. The patients were evaluated, 1 mL of brachial arterial blood was collected, and answers to a brief questionnaire were obtained. The blood was placed in microcentrifuge tubes and then brought to a brief boil before centrifugation at 10 000 rpm for 5 min in order to liberate the serum. They were then transported to storage at -20ºC, where they remained for 3 to 11 days.
Persons from the control group were residents of Pondicherry, an area endemic for bancroftian filariasis, as well as one control subject from a non-endemic area. Informed consent was obtained from each control subject, and minors were included with consent of their guardians.
The antistreptolysin O test was performed using an Olympus AU400 autoanalyzer according to the manufacturer’s instructions. The titers of antistreptolysin O antibody titers were graded as non-elevated (≤ 200 IU) and elevated (≥ 200 IU). Lymphedema was graded according to the following criteria: grade I, pitting edema that is reversible overnight; grade II, irreversible edema with no skin changes; grade III, irreversible edema with thickening of the skin; grade IV, irreversible edema with skin changes such as warts and cracks. Patients with lymphedema of grade I or II were grouped together and patients with lymphedema of grade III or IV were grouped together.
Results of an Og4C3 ELISA performed on the serum samples were not included in the analysis.
Results A total of 86 persons were studied, ranging in age from 16 to 66 in the control group and from 23 to 69 in the two groups of lymphedematous patients. The mean was 46 years (Table 1). Of these 86, 27 were control subjects with no history of parasitic infection. Thirty-five were filariasis patients with lymphedema of grade I or II. And 24 were filariasis patients with lymphedema of grade III or IV (Table 2).
The ASO test revealed an increasing number of patients with elevated ASO antibodies as the subject’s grade of lymphedema increased from 0 (control) to I or II to III or IV. In the control group, an elevated ASO titer was detected in 15% of the subjects. In lymphedema patients of grade I or II, an elevated ASO titer was detected in 23%; and in patients of grade III or IV it was 33% (Table 3).
ASO titer also increased with increasing frequency of ADL attacks during the past year (Table 4). In the control group (with no ADL attacks), an elevated ASO titer was detected in 15% of the subjects. In the group with one or two ADL attacks in the past year, an elevated ASO titer was detected in 33% of patients. In the group with three or four ADL attacks in the past year, an elevated ASO titer was detected in 36% of patients. And in the group with four or more ADL attacks in the past year, an elevated ASO titer was detected in 40% of patients.
Discussion Antistreptolysin O titers from the filarial lymphedema patients above suggest a clear correlation with both grade of lymphedema and with the frequency of acute ADL attacks. While control subjects showed an elevated ASO titer in only 15% of cases, the mild lymphedema group showed an elevated titer in 15% of cases and for severe lymphedema that number was 33%.
The pattern of increasing ASO titer was more evident in the correlation with frequent ADL attacks. Again while the control group showed an elevated ASO titer in 15% of cases, that number was 33%, 36%, and 40% of patients in the groups with 1 to 2, 3 to 4, and 4 or more ADL attacks in the past year, respectively.
An elevated ASO titer is an indication of recent infection with group A streptococci, which are normal inhabitants of the skin. Correlation between elevated antibodies to these bacteria and both higher grades of lymphedema and higher frequency of ADL attacks supports the growing evidence for secondary bacterial infection as a major cause of these attacks. Since 40% of the patients with 4 or more ADL attacks in the past year showed an elevated ASO titer, the ASO test may have some value as an indicator of susceptibility to future infection with group A streptococci. However as the ASO test is expensive and time-consuming, finding other means of determining a patient’s susceptibility may be preferable on a widespread basis. Nonetheless this study supports a streptococcal pathology of ADL and provides more support for controlling ADL by minimizing dermal bacteria through proper hygiene, footcare and antibiotics.
Acknowledgements Sincerest thanks are deserved on the part of Drs L.J. De Britto, J. Yuvaraj, and L.K. Das for their guidance throughout the project. The technical work of G. Vijayalexmi, B. Kumeresan, P. Kumaran, P.M. Azad, and M.K. Vijayalalexmi was indispensable and the endorsement of Drs S. Sabesan and M. Kalyanasundaram made the work possible. The reference librarian R. Sundarammal and her staff also helped with finding relevant scientific literature. Thank you to everyone at VCRC for being generous with your time, the most precious resource to be shared.
Works Cited
Gerber MA, Lolita S, Caparas, Randolph MF. “Evaluation of a New Latex Agglutination Test for Detection
of Streptolysin O Antibodies” Journal of Clinical Microbiology 1990; 28: 413-5.
Jamal S, Pani SP. “The clinical perspectives and research needs in lymphatic filariasis” Miscellaneous
Publications of VCRC 1990; 16: 29-41
Joseph A, Mony P, Prasad M, John S, Srikanth, Mathai D. “The efficacies of affected-limb care with
penicillin, diethylcarbamazine, the combination of both drugs or antibiotic ointment, in the prevention
of acute adenolymphangitis during bancrodtian filariasis” Annals of Tropical Medicine and
Parasitology 2004; 7: 685-96.
Nandha B, Sadanandane C, Jambulingam P, Das PK. “Delivery strategy of mass annual single dose DEC
administration to estimate lymphatic filariasis in the urban areas of Pondicherry, South India: 5 years
of experience” Filaria Journal 2007; 6.
Pani SP and Das LK. “Filarial Lymphoedema: Disability and Management” Lymphocon-10: Tenth Annual
Conference of the Lymphology Society of India, Bhubaneswar 2006; 24.
Suma TK, Shenoy RK, Kumaraswami V. “Efficacy and sustainability of a footcare programme in preventing
acute attacks of adenolymphangitis in Brugian filariasis” Tropical Medicine and International Health
2002; 7: 763-6
Suma TK, Shenoy RK, Varghese J, Kuttikkal VV, Kumaraswami V. “Estimation of ASO titer as an indicator
of streptococcal infection precipitating acute adenolymphangitis in brugian lymphatic filariasis”
Southeast Asian Journal of Tropical Medicine and Public Health 1997; 4: 826-30.
Wijesinghe RS, Wickremasinghe AR, Ekanayake S, Perera MSA. “Physical disability and psychosocial
impact due to chronic filarial lymphoedema in Sri Lanka” Filaria Journal 2007; 6.
LE
Grade
Number Mean Age Std Dev Min Max
0 27 45 12 16 66
I and II 35 46 10 23 65
III and IV 24 48 11 28 69
Table 1 Age of the study participants by lymphedema grade.
LE
Grade Frequency Percent Cumulative Percent
0 (Control) 27 31 31
I and II 35 41 72
II and IV 24 28 100
Total 86 100
Table 2 Frequency distribution of study participants.
LE Grade ASO Titer (IU)
Non-elevated (≤ 200) Elevated (≥ 200 IU) Total
0 23 4 27
85% 15% 100%
I and II 27 8 35
77% 23% 100%
III and IV 16 8 24
67% 33% 100%
Total 66 20 86
77% 23% 100%
Table 3 ASO grade by grade of lymphedema.
ADL Attacks ASO Titer (IU) Total
Non-elevated (≤ 200) Elevated (≥ 200 IU)
0 44 8 52
85% 15% 100%
1 to 2 10 5 15
67% 33% 100%
3 to 4 9 5 14
64% 36% 100%
4 or more 3 2 5
60% 40% 100%
Total 66 20 86
77% 23% 100%
Table 4 ASO grade by frequency of ADL attacks during the past year.
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