Prof. M. S. Khuroo
Research in medicine can has many facets and includes making inventions & discoveries, conducting randomized clinical trials, doing case-studies and wasting time in duplicating other’s-done studies. However, the most difficult studies are those done to break the age-old established dogmas, false beliefs and wrong practices in clinical medicine. For ages surgeons told us: “Never endeavor to needle-puncture a hydatid cyst as chances of anaphylaxis and death are high”.  In late nineties I set up the agenda to break this dogma and over the next 10 years defined needle-puncture technique (nicknamed as PAIR) as a simple non-invasive and credible procedure to effectively treat hydatid liver cysts and established its superiority over surgery.
Hydatid disease is caused by ingestion of eggs of the tapeworm, Echinococcus. granulosus. Dogs infected with the tapeworm pass eggs in their feces and eggs adhere to the hair, muzzle and paws of sheep and on ingestion, develop in to liver and lung cysts. Humans become infected in the course of playful and/ or intimate contact with the infected animal. Hydatid disease is a public health problem in Asia, the Mediterranean, South America and Africa. With immigration, the prevalence of the disease has increased in Europe and North America. Hydatid disease is highly endemic in canine-held state of Kashmir. 
Needle-puncture of hydatid cyst was not an easy task. I was sensitive to the dangers of this study and several points had to be realized. First intentionally puncturing a live cyst which had never been done in the history of medicine before could go wrong and have disastrous results for the incumbent and the team. Second any results had to be meticulously recorded in words and images to convince the skeptics. Third we had to study the procedure in great depth before needling the cyst.
Our first step was to find an agent which could kill the live cyst scoleces (which can cause disseminated disease if spilled in to the body cavity). We choose hypertonic saline and over next 2 years found that 20% hypertonic saline for 20 minutes consistently killed all scoleces in fluid collected from cyst at surgery. This involved observation of scoleces mobility on vital staining and intraperitoneal injection of fluid in mice and watch cyst growth (which takes around 6 months). Next we experimented an ingenious step-by-step method to puncture (P) cyst under ultrasound guidance, aspirate (A) the cyst quickly, install (I) equal amount of hypertonic saline in to the deflated cyst,  and reaspirated (R) the cyst contents after 20 minutes, completing the four steps in this famous PAIR technique. 1n September 1989 we were ready for the prime time and wanted to start with sheep liver cysts to guard the response. However, we were faced with a patient with large liver hydatid cyst and in whom surgery was absolutely contra-indicated due co-morbid diseases. We wrote the protocol, took necessary permissions from the ethical committee and explained the risks to the patient and family. We primed the patient with a large dose of anti-allergic drugs and punctured the cyst and completed all four steps of PAIR technique. Patient stayed well without any allergy, and anaphylaxis. In fact his symptoms related to his large cyst rapidly disappeared and the cyst collapsed in 48 hours and on serial ultrasound examinations disappeared in 3 months. The team was excited and encouraged and in the next 6 months we identified and performed PAIR in 21 such patients and the results were uniformly encouraging. There were no serious allergic reactions, there was no dissemination of disease, all cysts disappeared, and patients became asymptomatic and were cured of disease. Patients were treated without any sedation, stayed in hospital only overnight and experienced only a single needle prick. In contrast surgery needed general anesthesia, opening up of abdomen and a hospital stay of around 2 to 3 weeks.  Report of first 21 patients with PAIR technique found place in coveted American journal (Khuroo et al. Echinococcus cysts in the liver: Management with percutaneous drainage. Radiology 1991; 180:141-5). Lot of groups all over the World got interested in PAIR technique and safety and efficacy of the procedure was confirmed by all. In the next few years we refined the procedure by treating patients prior, few hours before and after the procedure with a scolicidal drug namely Albendazole and published these results in a highly respected American Journal (Khuroo et al. Gastroenterology 1993;104:1452).
Though PAIR technique was so acceptable with patients, medical fraternity wanted to know how this procedure stood against Surgery, the Gold standard of treatment. For this we conducted a randomized head-to-head study on 50 patients with hydatid cysts of liver (PAIR 25 and Surgery 25 patients) and evaluated multiple parameters in both groups.  PAIR was as good as surgery for cyst disappearance and cure of disease; needed less hospital stay; had less complications and better patient acceptance. These remarkable results were sent to Editor New England Journal of Medicine and as per my expectation were published in a matter of 8 weeks (Khuroo et al. Percutaneous drainage compared with surgery for hepatic hydatid disease. NEJM 1997;337:881-7). Skeptics did not stop here and questioned the long term outcome of this technique. For this we treated 95 cysts in 78 patients and followed up these patients for over six years and showed success in most of these patients with minimal immediate and long term complications and no recurrences or dissemination of disease (Khuroo MS. Percutaneous drainage of hydatid cysts. NEJM 1998;338;391-3).
While our team was busy in silencing the skeptics, PAIR technique was tested by hundreds of clinical units all over the World and found to be non-invasive, effective and safe to treat this disease. Large scale data on thousands of patients were published from Southern Europe where the disease is endemic in immigrants from North Africa. WHO was keen and did publish a chronicle depicting the steps of this new technique. I actively participated in this endeavor. This is how we broke the shackles of age-old dogma that needle-puncture of liver hydatid cyst is life threatening and established PAIR technique to treat cystic hydatid disease of liver. By now thousands and thousands of patients all over the world have benefited from this non-invasive, effective and safe technique.

Prof. M. S. Khuroo, MD, DM, FRCP (Edin), FACP, MACP (Emeritus). Director Digestive Diseases Centre, Dr. Khuroo’s Medical Clinic, Srinagar Kashmir, J&K, India.
Email: Khuroo@yahoo.com Website: www.drkhuroo.com

Lastupdate on : Mon, 6 Feb 2012 21:30:00 Makkah time
Lastupdate on : Mon, 6 Feb 2012 18:30:00 GMT
Lastupdate on : Tue, 7 Feb 2012 00:00:00 IST