Magnetic Resonance Imaging, Vol. 15, NO. 10, pp. 1193-1198, 1997 0 1997 Elsevier Science Inc. All rights reserved. Printed in the USA. 0730-725x/97 $17.00 + 00 ELSEVIER l Original Contribution PI1 SO730-725X(97)00180-X ‘H MAGNETIC RESONANCE IMAGING AND 31P MAGNETIC RESONANCE SPECTROSCOPY IN EXPERIMENTAL FILARIASIS AMITA SHUKLA-DAVE,* NIGAR FATMA,* RA.IA ROY,? S. SRIVASTAVA,$ R.K. CHATTEFUEE,* V. GOVINDARAIU,§ A. KASI VISWANATHAN,~ AND P. RAGHUNATHAN$ Divisions of *Parasitology, tMedicinal Chemistry, and $Toxicology, Central Drug Research Institute, Lucknow, India and $Department of NMR, All India Institute of Medical Sciences, New Delhi, India ‘H Magnetic resonance imaging and 31P magnetic resonance spectroscopy (MRS) have been carried out in experi- mental rodent iilariasis, i.e., Acanthocheibema viteae infectionin the rodenthost, Mastomys coucha The T,-weighted image of the infected hostshows fine hyperintense thread like structures of adult tilariid nests in the cervical region. “P MRS of normal and infected hosts,localized over the sameregion of interest, show sevenmajor peaks corresponding to phosphomonoesters (mchuiing ghrcose-6-phosphate+ fructose-tkphosphate, fructose~l-6-diphosphate, phosphorylchotie, and adenhte monophospbate or AMP), morganicphosphate, glycerophosphorylcholine, phos- phoenolpyruvate, phosphocreatine and nucleoside di- and tri-phosphates. Concentrations of phosphomonoesters (PMEs)are higher in the normal rodent compared with the infectedones. In vivo 31P MRS provides a non-invasive assessment of tissue hioenergetics and phosphohpid metabolism. 0 1997 Elsevier Science Inc. Keywords: ‘H Magnetic resonance imaging; 31PMagnetic resonance spectroscopy;Phosphorus metabolism; Acanthocheilonema viteae; Mastomys coucha; tilariasis. INTRODUCTION Lymphatic filariasis is a major public health problem and inflicts a considerable social and economic burden on many tropical and subtropical countries. It is currently estimated that 1.1 billion people are at risk of being infected, with 120 million people aheady infected in 73 endemic countries.’ The disease itself is not life threatening but causes chronic suffering, including episodic fever, lymphangitis, lymphad- en&is, epididymo-orchitis, etc., which may lead to massive swollen limbs, enlarged scrotum, breasts and clitoris. The conditions commonly known as elephantiasis are directly responsible for a huge loss of man-hours, productivity and economic well-being. Although insufficient to explain the clinical spectrum of filarial diseases, the pathophysiology of filarial infections is generally attributed to the presence of parasites, repeated attacks of lymphangitis, and/or the host’s immune response to the parasite. Recent strategies for fi- laria control are first being focused on the parasite and its detection, then on the pathogenesis of filarial diseases, and finally on both individual and mass chemotherapy? Mag- netic resonance imaging (MIU) has considerable potential for detecting live filarial parasites in situ and observing lymphatic alteration after drug therapy in filariasis; this potential has been exploited by only a few investigators. Case et al.3 have visualized lymphatic abnormalities in ferrets infected with Brugiu malayi, while Tanoura et al? examined the potential utility of MR to monitor response of hyperplastic lymph nodes to AMl-227 in ferrets infected with filariasis. Eberhard et al5 used this conventional tech- nique MIU for imaging microfilaria-positive chimpanzees and mangabey monkeys to detect adult Onchocercuvolvu- Zusworms or nodules. The aim of the present study is to employ MRI and magnetic resonance spectroscopy (MRS) to delineate the morphological and metabolic characteristics of filariasis (Acanthocheilonemu viteae) in the rat (Musto- mys coucha). MATERIALS AND METHODS Host-parasite model. A. viteae filarial larvae were transmitted to Mustomys coucha by the tick vector, Or- nithodorus moubata6” RECEIVED 5/21/96; ACCEFTED 7117197. Drug Research Institute, Chattar Manzil, P.O. Box 173, Luc- Address correspondence to: R.K. Chatterjee, Ph.D., Central know 226 001, India. E-mail: root@csdri.ren.nic.in 1193