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Who Put the Tank in the Tiger?

2003; Lippincott Williams & Wilkins; Volume: 49; Issue: 1 Linguagem: Inglês

10.1097/00002480-200301000-00003

1538-943X

George E. Schreiner,

This story begins with the Maharajah of Rewa, India, who had heard of sightings of white tigers in wooded land under his control. With insight worthy of a corporate executive marking sales, he put up a map of the area and inserted a pin wherever a sighting occurred. When the pins began to cluster in an area, he commissioned trappers to trap cubs on the theory that if this were a recessive gene, propinquity might lead to a cross breeding and the obtaining of a white tiger. This plan and action demonstrated a sophisticated knowledge of genetics and inbreeding. The first mating produced a white tiger that did not live. This was communicated to a Washington gentlemen who was a benefactor of the National Zoo and who chartered a plane and flew back with an orange tiger named Samson, who was a litter mate of one of the first born white tigers in the palace zoo in Govindgarh. Samson was mated to the only eligible female tiger in residence at the Washington National Zoo. In retrospect, she had an increase in white hair over the abdomen and may have been a random selection of a tiger with the recessive gene. These matings produced several white tigers, none of whom survived. The first ones had a bone marrow disease, possibly aplastic anemia, an immunologically oriented sensitivity disease that may have presaged subsequent events. Meanwhile, at Govindgarh, a white male named Mohan, the father of Samson, continued mating with the orange female Bengal. They produced 10 cubs in three litters from 1953 to 1956, all orange. The Maharajah then paired Mohan with one of Mohan’s orange daughters, Radha, who gave birth to one white male and three white females, Rani, Sukeshi, and Mohini. Mohini (Figure 1) was purchased for the National Zoo by one of its benefactors. Mohini was not an albino but an autosomal recessive for the white coat. She had black stripes, and her eyes were icy blue, not pink. Samson, who had come to the National Zoo in 1963, was also a known heterozygote because he had fathered white cubs. To help you understand the inbreeding, Samson, besides being Mohini’s mate, was her uncle and half-brother. He was also Ramana’s father, great-uncle, and half-uncle, who when later bred to Mohini was already her son, cousin, and half-nephew. Figure 1: Mohini, a female tiger, autosomal recessive for the white coat.Samson had accelerating weight loss, lethargy, polydipsia, polyuria, and polyphagia. His serum glucose was elevated and a diagnosis of diabetes mellitus was made by the resident DVM, the late Dr. Clint Gray. A consultant from the University of Pennsylvania School of Veterinary Medicine saw him and prescribed Orinase, which proved to have no benefit; he was then given insulin, again no benefit ensued, and his course was inexorably downhill. I was involved when Dr. Gray called me in consultation because he noticed the polyuria and wondered if there could be some kidney involvement. My first request after seeing Samson (Figure 2) was that of any good clinical nephrologist: “Please get me a clean catch urinary specimen.” The veterinarians were baffled as to how that could be obtained in clean fashion from a tiger. I then did what every good clinician should do: I went to the zoo and simply watched Samson for most of an entire day to learn his habits. Figure 2: A uremic Samson before treatment.There was a small door at the back of Samson’s cage, through which he was led for his public appearances and for feeding purposes. The floor of the cage had a modest slope in all directions toward a central drainpipe in the middle of the cage. It was obvious that any liquid material would run downhill toward this drain; the question was how to keep it clean in the process. I also observed that tigers have a distinctive habit of eating their meal, which in this case consisted of 10 to 12 pounds of raw beef, and then proceeding, as they do in the wild, to urinate on the remaining carcass, which in this case was the feeding dish. I took advantage of these observations by having the cage thoroughly scrubbed with Lysol and rinsed with sterile water. I then brought a stainless steel surgical dish from Georgetown Hospital that had been autoclaved as it would be for use in an operating room. I arranged to have a clean piece of raw meat that had been sterilized by x-ray placed in the sterile pan to which was attached a sterile fishing line. As the rear door was opened, I pulled the meal (pan and beef) along the outer perimeter of the cage so that I would have control of its movement. Samson dutifully followed, although he was so clinically uremic he was barely able to walk. He ate the meal, however, and then moved toward the eating pan to do his usual thing. I pulled the pan quickly away and the midstream urine hit the clean floor and ran toward the center drain, which had been blocked by a piece of sterile plastic; it remained there in a small pool. Samson was then enticed back along the edge of the cage and out the rear door. I put a long piece of sterile intravenous tubing on a 50 cc syringe, withdrew the urine sample, placed it in a sterile container, and took it back to the Georgetown renal laboratory. A sample drawn with this good technique was cultured in the Georgetown Bacteriology lab and proved to be sterile. The urine contained glucose and 300 mg % protein, together with fatty and cellular casts. Figure 3 shows the fat globules in a cast under high power. The relative size of the casts gives an idea of the large diameter of a tiger nephron. I also tested Mohini and Ramana, who had traces of protein in high specific gravity urine, at the National Zoo, and I tested unrelated tigers from Washington and two from San Diego, kindly supplied by Dr. Irwin Arias, who took his vacations doing experimental work in hepatology and metabolism at the San Diego Zoo. In addition, I tested two lions and a tiger from the San Francisco Zoo. Only Samson and Ramana had fat droplets in a cast in any of the urine samples I examined. We took blood from one of Samson’s tail veins, and the initial blood urea nitrogen (BUN) in the National Zoo lab was over 150. Repeated BUN levels taken in our laboratory varied from 170 to 200, with the highest recorded at 234 on November 17, 1966. After poor results with the diet and poor returns for the initial attempt at peritoneal dialysis on November 21 and 22, Samson’s BUN had only fallen to 102 and 104 mg %, respectively. Because the diet is almost exclusively meat, the normal BUN in a domestic cat is around 20, and I found values in lions and big cats in the range of 60 to 90 mg % after eating. The initial creatinine in Samson was 6.5; the highest obtained was 8.4 on September 23, 1966, and our initial attempts at dialysis brought the values down to 5.2 on November 21, 1966. The CO2, initially 3–7, rose to 20 after a month of perfusion and reached 27 on November 21, 1966. The hematocrit fell gradually from 37 to 25. Two-thirds of the serum proteins were beta and gamma globulins, and the albumin was 1.6 gm %. Figure 3: Fat globules, taken from a urine sample, in a cast stained with oil red-o under high power.Our initial treatment consisted of intraperitoneal bicarbonate, glucose, and hydration; the giving of vitamins; and a somewhat failed attempt to get him on a lower protein diet. The only thing that Samson would readily eat was his usual 12 lb of raw steak, and the only substitute he found acceptable was a whole, skinned rabbit that proved to be lower in protein and did have a modest effect on reducing his BUN. We therefore realized that the conventional peritoneal dialysis of running fluid in, allowing some time for it to equilibrate, and then withdrawing it, so called intermittent peritoneal dialysis, would not work, as we were unable to get any returns. I then decided to work with a squeeze cage, to which we led him again with a plate of food. With shoulders fixed, he could not injure me, so I was able, with him standing on all four legs, to put a #12 needle, with plastic tubing attached, into his peritoneal cavity through the midline of his abdomen. Through this I began the inflow phase of his peritoneal dialysis. When I failed to get any return on the outflow phase after installation of successively 2, 4, and 8 L, I finally put in 12 L of peritoneal dialysate and let him walk around, lie down, and live normally for 24 hours. Realizing that intermittent peritoneal dialysis would be impractical, I had the inspiration to ask, “If we can’t go in and out, why not go out and in, with a single needle stick each day?” I could then drain the peritoneal dialysate through the #12 needle and instill the next batch of peritoneal dialysate before removing the needle. With this regimen, Samson gained weight for the first time, lost his lethargy, took an interest in public appearances, and improved his chemistries (Figure 4). We hastened the administration by placing the Dianeal in a sterile tank. We could run the Dianeal in by gravity through his abdominal needle (out/in ambulatory peritoneal dialysis versus the conventional in/dwell/out peritoneal dialysis). Figure 4: Samson after considerable improvement and weight gain after a period of ambulatory peritoneal dialysis. He was able to fulfill his usual exhibit time and expressed his usual personality.Because of the impending holiday season and marked increase in clinical work at Georgetown, I was unable to personally continue the administration of the chronic ambulatory peritoneal dialysis. Zoo officials taught Samson’s keepers the mechanics of performing the procedure, and Samson’s clinical appearance continued to improve. However, the zookeepers had no medical background and were given a government holiday preceding Thanksgiving. No dialyses were done over the holiday, Samson received only 3 L on November 26, and, unhappily, he was found dead in his cage on the morning of November 27. A blood sample, which may have been postmortem, showed hyperkalemia over 10; in the 16 previous blood samples, the highest potassium had been 5.0 mEq/L. The autopsy was performed at the Armed Forces Institute of Pathology by Lieutenant Colonel F. M. Gardner and signed off on by Major General Joe E. Lumberg, MCUSA. The complete findings were published in the Journal of the Smithsonian Institute. Our major clinical diagnosis was uremic syndrome probably due to interstitial nephritis with oliguria, treated successfully but temporarily with ambulatory peritoneal dialysis. The major necropsy diagnosis was chronic interstitial nephritis. The gross autopsy findings were as follows: “The lungs had miliary calcified nodules approximately 1 mm in diameter scattered throughout the parenchyma. The surface of the lung was gray due to the presence of anthracotic pigment. The bronchial nodes were black due to the pigment. The liver was tannish-yellow in color and had the normal lobular architecture. The bile ducts were patent. The anterior margin of the tongue was purple and ulcerated. The mucosa of the duodenum had a spongy appearance and contained many small cysts filled with a clear tenacious fluid. The jejunum had several small raised hemorrhagic areas, 5 mm in diameter. The capsule of the kidney was very thick and fibrous. The surface was pitted in many areas. The cortex was narrow and the corticomedullary junction was indistinct. The cortex and medulla had an increased amount of fibrous tissue. There were no gross lesions in the heart, aorta, spleen, thyroid, parathyroids, pituitary, adrenals, pancreas, urinary bladder, genital system, brain, bone marrow, bones, joints, musculature, or eye.” On microscopic examination, the lungs had a considerable amount of mineralized material in the alveolar septal walls. The septal walls were also thickened because of a proliferation of fibrous tissue and septal cells. Mononuclear phagocytes were numerous in the alveoli of the involved areas. A few areas included exudate containing cholesterol clefts. Anthracotic pigment was plentiful. The liver was moderately congested, and there was also dissociation of the hepatocytes. The spleen and lymph nodes were depleted of lymphoid elements. There was hyperplasia of the reticuloendothelial cells. The kidney had a thickened fibrous capsule. Most of Bowman’s capsules were thickened because of the deposition of an eosinophilic hyaline material. Many of the tubules were dilated and contained eosinophilic protein or hyaline casts. There were many areas that had been scarred, and the normal parenchyma had been replaced by fibrous tissue. The interstitium was infiltrated with lymphocytes, plasma cells, and a proliferation of fibroblasts. There were also foci of mineral material. Brunner’s glands in the duodenum were dilated and formed cysts that were lined by flatted epithelial cells. The lamina propria of the small intestine had an increase of fibrous tissue. The jejunum had foci of disruption in the continuity of the mucosa. These foci were infiltrated by inflammatory cells and contained a lot of basophilic necrotic cellular debris. The thyroid, parathyroid, heart, aorta, pancreas, adrenal, urinary bladder, bone marrow, brain, and eye had no significant changes. Table 1 summarizes the final microscopic diagnosis.Table 1: Final Microscopic DiagnosisDr. Heinz Bauer from the Pathology department at Georgetown did immuno-cyto-chemical studies with fluorescent antiserum prepared in rabbits to tiger 7S gamma globulin by Dr. Nathan Zwaifler, director of the rheumatology division, who fractionated whole tiger serum on a DEAE column. Controlled stains showed large amounts of 7S gamma globulin in tubular casts and granular deposits in glomerular loops. In a personal discussion, Dr. Bauer and I both agreed that a genetic trait may have caused the unusual capsular and interstitial fibrosis that appeared more primary than reactive. In fact, it resembled in many ways the lesions that had been seen in the kidneys and other organs in human patients with Scleroderma, which I had described in the American Journal of Medicine in 1957. Dr. William Deiss, the Chairman of the Department of Medicine at the University of Texas at Galveston, a longstanding friend and occasional fishing companion of mine, had called me that year and fortuitously asked me to accept one of his chief residents who wished to have training in nephrology. Dr. Deiss had initiated an excellent plan for Chief Residency that consisted of 6 months of administrative responsibility for house staff and 6 months selected training in some specialty of the resident’s choice. Dr. Jack W. Moncrief came to our laboratory as a Renal Fellow and happily was with us at the time that our experiences with Samson and chronic ambulatory peritoneal dialysis at the National Zoo were taking place. He later returned to Texas and, with Robert Popovich, worked out the application of chronic ambulatory peritoneal dialysis. Samson, our tiger patient, was clearly chronically uremic; he certainly was ambulatory when awake, and he had a single daily peritoneal dialysis with an out/in rhythm. Initially the volume of Dianeal was 12 L per 24 hours in a human-sized, 285 lb animal that, when healthy, weighed 385 lb. He was then infused daily with 2–8 L or more from October 7 to November 27, 1966. Therefore, he would seem to be the first instance of chronic ambulatory peritoneal dialysis. In summary, we put the tank in the tiger. Acknowledgments The author thanks the following individuals: Dr. Clint Gray, DVM, for calling us in consultation; Dr. Theodore Reed, the Zoo director who is also a DVM, for unstinting cooperation in all aspects of this case; Dr. Clint Fields, a later Zoo director and Dr. Dick Montali, head of Nephrology and Pathology, for assistance in finding and checking old records; Lieutenant Colonel F.M. Gardner and Major General Joe M Blumberg of the AFIP, for providing the autopsy records on Samson; Dr. Irwin Arias, for providing samples from the tigers and lions from the San Diego zoo, where he regularly worked on research projects; Mrs. Betty Mendelson, who typed many of the original tables and legends; Mrs. Marie Mills, who did the final typing of the current manuscript; the late Mr. Jack Bird, who went with me to photograph Samson during one of my earliest visits; Dr. Eli Friedman, current Editor of the ASAIO Journal, who was kind enough to suggest the submission of this manuscript; and Ms. Pauline Dopler of Georgetown University Clinical Laboratory and Dr. Dirk Van Peenan and his staff at his Navel Medical Research Unit, Bethesda Naval Hospital, for additional laboratory support. The original dialysis fluid was made by hand from intravenous dialysis solutions at Georgetown Hospital, and the continuing ambulatory dialysis was conducted with Dianeal, kindly furnished by Baxter Laboratories.