By V. Lars. Washington College.
It has been estimated in the past that classification is clinically not very useful and often about 5–10% of children infected with Shiga-toxin-pro- confusing since there is significant overlap between ducing E 80 mg super levitra amex. This seems to be at least in part related other infectious and noninfectious conditions as listed to the higher incidence of positive fecal cultures for in Table 16 discount 80 mg super levitra with mastercard. Interestingly super levitra 80 mg overnight delivery, by far the minority of indi- cating through the intestinal epithelium  purchase super levitra 80mg without a prescription, binding viduals (less than 10%) exposed to E. The Shiga-toxins 1 and 2 produced by of schistocytes on the peripheral blood smear. The days, nine out of ten children present with symptoms first step in this cascade of events is characterized by of diarrhea. In more than 50% of those cases, the intestinal infection of Shiga-toxin-producing E. For that reason, keeping a high index severe, crampy abdominal pain mimicking appendici- of suspicion early is very important to confirm the diag- tis or inflammatory bowel disease. Stool should always be sent specifically to assay early stages of the disease or in the absence of bloody for E. The colitis respon- The anemia is nonimmune mediated and a direct sible for the severe diarrhea is often very painful and Coombs test is negative. These include a complete blood in as many as one-third of children presenting with a count with differential and a reticulocyte count, which variety of clinical findings including seizures, altered is usually elevated indicating an appropriate bone mar- level of consciousness, visual and auditory hallucina- row response. Generalized seizures compared with little is known about the effects of initial leukocyto- partial seizures seem to have a better prognosis . A urinalysis to assess for hematuria, nuria for about 1 week, but it can persist for several hemoglobinuria, and proteinuria should be performed. Microscopic review of a freshly voided urine speci- men is very helpful to look for the presence of hyaline, granular and cellular casts, which can be indicative of 16. By the time the clinical course becomes more Salmonella, and Shigella gastroenteritis. It was first described by emphasis needs to be placed on prevention of overcor- Moschcowitz in 1924 . In other words, once fluid losses have been the same histological lesions defined by subendothe- replaced and perfusion is restored, the strategy needs lial space widening and intraluminal thrombi . Differentiation of the two entities is very important to decide on appropriate therapies and to 16. Rarely, patients may present with right lower quadrant pain with preceding diarrhea and From a patient care perspective, early transfer of the be diagnosed with appendicitis . Balancing intake Given the complexity of the disease and the lack of (oral and intravenous fluids) and output (urine, stool, reliable markers of severity of the clinical course to and insensible losses) at set close intervals will allow be expected, inpatient unit admission for further man- an accurate assessment of the child’s fluid status and agement should be considered in virtually all children early detection of decreased urine output in case of once the diagnosis is established. This is of importance to avoid potential iatro- urine output with and without azotemia, electrolyte or genic fluid overload. An accurately measured weight acid–base imbalance, and presence of clinically sig- of the patient, recorded once or twice per day, can nificant blood pressure elevation. Usually, transfusion can tered as the degree of hyponatremia is correlated with be delayed as long as oxygen delivery to the tissue is the severity of neurologic injury . Intravenous sufficient and there is no significant cardiovascular or medication infusions should be, if possible, mixed hemodynamic compromise in the patient. On the other in isotonic saline once hyponatremia is recognized hand, a recent study by Grant et al. Repeat blood work to assess renal in the state of acute anemia, adaptive changes compen- function and serum electrolytes, and progression of sate for decreased oxygen delivery. It is unclear if this anemia will influence the decision to place central adaptive state could influence the overall outcome in venous access or a peritoneal dialysis catheter. Even though it is at times difficult or a progressively positive fluid balance in the setting to distinguish between symptoms related to the under- of decreased urine output. Placement of invasive lines lying disease and a true reaction to transfusion, the should only be undertaken by experienced profes- incidence of transfusion-related reactions has been sionals as bleeding complications are not infrequently reported to be as high as 1. Another important factor to consider when mak- avoid difficulties due to marked volume overload and ing the decision to transfuse packed red cells is the edema and might decrease the risk of procedure-asso- strong potential of bone marrow suppression in a ciated complications. Presence of hypertension or res- patient who has an appropriate bone marrow response piratory involvement might require the insertion of an indicated by an elevated reticulocyte count. Posttransfusion hematocrit levels above 30% potential need for future transfusion. There is ongoing debate about the optimal diu- that prolonged thrombocytopenia is associated with an retic prescription. It appears that in hemodynamically increased risk for long-term renal abnormalities . A trial of furosemide at a dose of 2–4 available data caution treating providers to withhold −1 −1 mg kg dose or as continuous drip should be consid- platelet transfusion given the potential to increase for- ered. The addition of a downstream thiazide diuretic mation of hyaline platelet-fibrin thrombi and worsen- can potentially further enhance urine output. In a ing of microthrombi by transfusing additional platelets recent meta-analysis of patients with acute renal fail- [24, 27]. An absolute indication for platelet transfusion ure (including critically ill patients), loop diuretics in the setting of documented thrombocytopenia is acute did not affect mortality or the need for renal replace- and clinically significant bleeding, which is rarely ment therapy but shortened the duration of dialysis seen in clinical practice; most centers also agree on and improved urine output . However, since the platelet transfusion as a prophylactic measure before majority of the patients in these studies were not criti- performing an invasive procedure such as placement cally ill, conclusions for this particular population are of a central venous catheter. These has been established, focus is on conservative medical advances are due to a combination of several factors, management of acute renal failure. Renal failure can including availability of continuous forms of hemodi- present either in the oligoanuric form or nonoligoa- alysis in children, especially younger children, quality nuric form. Accurate fluid management is critical for of vascular access, and our improved understanding of both groups since renal failure can progress toward the pathophysiology of individual disease entities . Several factors need to be taken into close documentation of the fluid balance by meas- consideration, most of all modes of dialysis and early uring intake and output including insensible losses provision of proper access by the pediatric intensiv- (350–400 cc m−2); this is important to avoid volume ist or pediatric surgeon. Having central venous access overload, one of the most common indications for available early will avoid difficulties with placement in initiation of renal replacement therapy. It is helpful to decide on a mode mal recommended daily allowance adjusted for age. Studies have also shown that patients Abnormalities in a baseline cholesterol and triglycer- with less volume overload and lower levels of uremia ide levels might warrant restriction of lipids, which is might have an overall better prognosis [23, 46]. It is important to remem- dinated with the placement of dialysis access to avoid ber that all modalities of dialysis have certain poten- additional procedural sedation. In the presence of hyperkalemia, diuretics, therapy under the direction of the Pediatric Nephrologist bicarbonate and potassium binding resins among and Intensivist. The choice of dialysis mode depends others (see chapter on hyperkalemia) should be used on the individual experience of the treating providers until proven noneffective and the decision to proceed and center. It is important to remember preferred mode unless abdominal complications, most that insulin with glucose and treatment with bicar- often serious colitis requiring surgical intervention, bonate only lead to a temporary decrease in extra- pose a contraindication to this form of renal replace- cellular potassium levels by intracellular shifting but ment therapy. Children with not require the presence and experience of specialized acute renal failure in the intensive care unit are fre- staff as in the other forms of renal replacement ther- quently malnourished, often due to a combination of apy. The peritoneal dialysis catheter can be placed at an exhausting primary disease and malabsorption of the bedside or in the operating room and is essentially nutrients . In the past, fluid restriction to avoid a ready for use immediately after placement. Peritoneal positive fluid balance in a child with oligoanuric renal dialysis solutions are available from a number of man- failure was one of the mainstays of supportive care. It seems therefore intuitive that early Three variables allow adjustment of the ultrafiltration dialysis in oligoanuric children and avoidance of pro- volume and clearance: dextrose content of the solu- longed nutritional restriction might be a reasonable tion, fill volume, and frequency of exchanges. Continuous forms of renal replace- 5 Progressive and profound azotemia ment therapy are quite gentle and used in the coop- 6 Need for transfusion of blood products in the erative child but require the presence of experienced setting of oliguria personnel. Sedation and potentially intubation might 7 Removal of inflammatory mediators in the be required for a younger child to successfully perform critically ill child the procedure, interventions that are rarely necessary Chapter 16 Hemolytic Uremic Syndrome 227 with peritoneal dialysis. Care must be taken with respect to bleeding tiate complications from primary disease as opposed complications, clotting of the circuit, and infection. A system-based approach is helpful to Young age and cardiovascular instability of the child organize and manage these issues. A detailed discussion on the topic of hyperten- requires nursing staff with experience in hemodialysis sion can be found elsewhere is this book. Fluid removal and electrolyte shifting occur over the pathogenesis of hypertension: First, hyper expan- a much shorter time compared with the other forms of sion of the intravascular volume secondary to an imbal- dialysis, making this a suboptimal mode of therapy in ance of fluid needs and inability to excrete and second, the hemodynamically unstable patient. Depending on the severity of vigorously debated but no consensus approach has the child’s illness and degree of blood pressure eleva- emerged so far.
Parasite ova originating from the respiratory tract may be coughed up order super levitra 80 mg without prescription, swallowed and found in the excrement discount 80 mg super levitra with mastercard. The cutting edges of tobacilli trusted 80mg super levitra, staphylococci order 80 mg super levitra with amex, streptococci and Bacillus the rhamphotheca are called the tomia. In large parrots, the in Galliformes, Columbiformes, Falconiformes, 140 complete rhinotheca is replaced in about six months, Strigiformes and Corvidae. The rate of growth of fail to reveal some important microbes that can cause the gnatotheca is about two to three times faster than that of the rhinotheca. A technique for identifying mycobac- ment of the rhinotheca has been described in caper- caillie (annually)4 and Suriname finches. Detection of campy- lobacter can be augmented by the use of Hemacolor; the bacteria appear S-shaped or in gull-wing form. In gallinaceous birds, a deformed upper mandible has been associ- Combine 4 grams of feces and 12 ml of 15% sputofluol (Merck) ated with embryonic deficiencies of folic acid, biotin Gently mix for 30 minutes or pantothenic acid. Crusty, scab-like lesions in the Centrifuge for 5 minutes 10,000 rpm corners of the mouth are considered a definite sign of Make smear of sediment 5 biotin or pantothenic acid deficiency in these birds. Stain with Ziehl-Neelsen Examples of acquired lesions that can lead to malfor- mations or necrosis of the beak include punctures, lacerations, splits and avulsions. Traumatic frac- tures, especially of the mandible, occur frequently in psittacine birds that get caught in hooks suspended from the ceiling of their enclosures or as a result of The Beak fighting. Any bacterial, mycotic, viral or parasitic pathogen that damages the germinative layers of the beak can cause developmental abnormalities. In psittacine growth in psittacines, especially budgerigars, has birds, the upper and lower jaws are connected to the been associated with liver disease (Figure 19. The keratinized sheath cov- The rhinotheca may overgrow in hardbills main- ering the upper and lower beaks is called rhamphoth- tained in an indoor environment and provided soft eca and can be divided into the rhinotheca (maxillary foods. Chronic rhinitis may lead to permanent defects in the adjoining germinative layer of the rhinotheca (Figure 19. Dysphagia, which may be recognized clinically as an accumulation of food under the tongue, can be an indication of rhamphothecal dys- function. The Oropharynx and Salivary Glands Anatomy and Physiology49,101 Birds lack an oropharyngeal isthmus, and the oral and pharyngeal cavities are combined to form an oropharynx. The walls of the oropharynx contain numerous mucus-secreting salivary glands (Figure 19. The palate contains a median fissure called the choana, which connects the sinuses to the glottis. Just caudal to the choana is the infundibular cleft, which is the common opening of the auditory tubes. Swal- with a nine-month history of progressive sneezing and nasal dis- lowing involves a rapid rostrocaudal movement of the charge. The feathers around the beak were moist from a serous tongue and the larynx, assisted by sticky saliva and nasal discharge. The rhinotheca had a deep groove that extended from the nostril to the rostral commissure of the upper beak caudally directed papilla on the tongue, laryngeal (arrows). During swallowing, the choana, layer of the rhinotheca had been involved in a disease process for infundibular cleft and glottis are closed. A mixed population of gram-positive and gram-negative bacteria were cul- glands secrete mucus and, in some species, amylase. The bird responded to nasal flushing, During the breeding season, the salivary gland of systemic antibiotics, frequent exposure to fresh air and sunlight swifts temporarily enlarges to produce an adhesive and being removed from a smoke-filled environment. The nests of some of the cave swiftlets of Southeast Asia are made entirely vitamin D and calcium deficiencies. The Grey at the commissure of the beak have been described Jay produces large quantities of mucus that are with trichotecene mycotoxicosis, avian poxvirus and formed into boluses and stored on the sides of trees trichomoniasis (cockatiels). Diagnosis can be achieved by identifying elementary bodies (Bollinger bodies) in impression smears prepared from lesions and stained with Wright’s stain or by the Gimenez method. Histologic identification of basophilic and eos- inophilic intranuclear inclusion bodies is suggestive. A diagnosis can be made by staining suspected material with the Gram’s or Ziehl-Neelsen methods (see Table 19. A case of malignant fibrohistiosarcoma located on the tip of the tongue in a seven-year-old Brown-throated Conure was successfully removed by radiosurgery. The tongue, pharynx, esophagus and ingluvies of Falconi- depressor mandibulae muscles (arrows) have been transected bi- laterally to allow the jaws to be opened, revealing the 1) upper formes, Psittaciformes, Galliformes, Passeriformes beak, 2) openings of the seromucous glands, 3) choana, 4) rima and Anseriformes. Abscesses occur in multiple locations includ- ing a) perichoanal, b) pharyngeal, c) periglottal, d) lingual, e) of the beak and diphtheritic membranes in the phar- lateral-ventral lingual and f) sublingual tissues. In in some passerine chicks is brightly colored, with Strigiformes, Synhimanthus (Dispharynx) falconis distinctive markings that disappear when the chick has been reported in the oropharynx. Lesions containing the adult Oropharyngeal Diseases nematodes can be found in the mouth, esophagus and crop. Oral cavity Ulcerative, necrotic, diphtheritic Most species, particularly neonates, Esophagus immunosuppressed animals Duck enteritis virus Oral cavity Ulcerative Ducks Sublingual salivary glands Herpesvirus Oropharynx, Esophagus Diphtheritic Owls Proventriculus Lice Oral cavity Stomatitis Penguins (Piagetiella peralis) Leeches Nasal cavity, Conjunctiva Hyperemia at attachment site Anseriformes (Theromyzon spp. Tongue, Frenulum Granulomas Psittaciformes, Falconiformes Hard palate Galliformes Neoplasias All locations Masses, ulcerative Most species Papillomas Oropharynx, Esophagus Masses Psittaciformes Proventriculus Pigeon herpesvirus Pharynx, Esophagus Diphtheritic Pigeons Poxvirus Mouth Diphtheritic Galliformes, Psittaciformes, Esophagus Passeriformes, Raptors, Columbiformes Trematodes Oral cavity Stomatitis Ciconiiformes (Cathaemasia spp. Some authors suggest that hypovitaminosis A is un- Hypovitaminosis A likely in pigeons because these birds efficiently me- tabolize this vitamin. Affected birds are usually fed all-seed diets with a large percentage of sunflower the condition progresses, the duct systems fill with seeds. Treatment should include parenteral vitamin masses of degenerate lymphoid and inflammatory A and the use of a formulated diet. Mucosal lesions that appear similar to those caused Lesions associated with hypovitaminosis A in galli- by hypovitaminosis A have been described on the naceous birds first appear in the pharynx and are palate of pigeons and are referred to as sialoliths (see largely confined to the mucous glands and their Color 13). The epithelium is replaced by a stratified substrate mixed with cellular debris are clinically squamous epithelium that occludes the ducts of the recognized in approximately one percent of pigeons. Fish bones may lodge in the pharynx or Foreign Bodies proximal part of the esophagus causing dysphagia. A thorough oropharyngeal examination and Stomatitis radiographs may reveal the foreign body. Stomatitis in birds has been associated with the consumption of hot foods, ingestion of oil and inges- A string looped around the base of the tongue and tion of caustic substances. Beak ne- can become lodged around the tongue, causing avas- crosis has been described in pigeons and gallinaceous cular necrosis. The bird’s feathers were in poor condition, and the bird appeared to be hungry but would eat reluctantly. On physical examination, the defect in the palatine area of the beak appeared to contain a foreign body. The splinter was removed and the wound was accumulate in the damaged tissues and create a nidus for secon- debrided and flushed. In this Umbrella Cockatoo, days of presentation, and it began topreen normally within a week. The grad- Lacerations of the Tongue ual accumulation of fine particles of food along the Lacerations of the tongue have been encountered in inner edge of the lower beak leads to secondary infec- psittacine birds and may be due to mate-induced tion and necrosis of the beak. Feeding pelleted ra- trauma, automutilation during the excitement phase tions prevents the problem. The tongue of turkey of post-anesthetic recovery or gnawing on sharp ob- poults fed a finely ground mash may be curled back- jects. The tongue is highly vascular and bleeds pro- ward by an accumulation of food on the floor of the fusely if damaged. Many trichotecenes, notably T toxin, can cause caus-2 tic injury to the alimentary mucosa. Yellow erosive Glossitis Gelatinosa Circumscripta and exudative plaques with underlying ulcers lo- A gelatinous mass may be found on the dorsal aspect cated near the salivary duct openings on the palate, of the tongue in five- to twelve-week-old ducklings tongue and buccal floor are characteristic lesions. The precise etiology is undetermined, Thick crusts of exudate may accumulate along the 103 but a multi-deficient diet has been suggested. Experimental transmission occurs by inocu- lation of tissue suspensions and by direct contact.
If the bird tries to move or bite generic super levitra 80mg without a prescription, the visual signal is offered with the word “stay” buy super levitra 80 mg with visa. If the bird responds (a response in this case is lack of movement) discount super levitra 80mg without a prescription, it should be verbally praised discount 80 mg super levitra with mastercard. When the “stay” command is mastered and the bird has successfully responded ten times in a row, the training can move to Stage 2. First issue the “stay” directive, even as the hand-held perch is being presented (without the “up” command). If the bird does not step up, gently slide the perch closer into the bird’s abdomen to force it to step up on the perch. Repeat the process, going from the hand-held perch to a stand perch using the same commands, “stay” (with the stop sign) and “up” for moving to the perch (at the discretion of the trainer, not the bird). The bird can then be trained to “stay” on the perch stand, for increasing periods of time. Stage 3 Using a feather or a stick, the wing is slightly opened away from the bird’s body, while the command, “wing” is given. The same series of exercises can be performed to enable the bird to lift a foot on the “foot” command. Eventually, the bird will respond comfortably so the wings and nails can be trimmed without restraint. Stage 4 When “stay,” “up,” “wing” and “foot” are performed success- fully, the bird is ready to receive a hood. A large soft article of an acceptable color (towel, piece of opaque plastic, etc) is gently draped over the bird’s body while the command “hood” is given. The article is left on for only a few seconds at first, gradually increasing the time of each phase as the material is maneuvered up over the head. The size is gradually decreased so a small “hood” is actually placed over the head, obscuring the bird’s vision. Over time, the trainer should be able to touch and walk around with the hooded bird on the hand-held perch, and even trim the wings or nails and transfer the bird to a new person without incident. If the bird is sible, the bird may be hooded or taken to a dark biting out of fear the trainer must first gain its time-out location prior to screaming periods. If it is biting because it is “spoiled” or remainder of the training is routine, with special needs to show dominance, it must first be trained to emphasis placed on the trainer leaving the room for respect the client. If the bird runs up the perch and increasing periods of time during the stay command. Yelling back at a bird is never useful, Screaming as it will quickly learn that screaming is a good way Screaming is a serious behavioral problem, espe- to get attention. Once medical causes of feather picking have been ruled-out, psychologic causes should be explored. The two most common primary causes of feather picking in the author’s experience are frustrated mating in- stincts and lack of proper training (Figure 4. Sexual frustration is common in birds, especially in cockatoos and many domestically bred birds. Pro- grammed in the wild to be constantly with a mate, a bird becomes distraught when its “person mate” is gone much of the day. It may also become jealous of other family members or maladjusted following a change in environment (eg, change of enclosure loca- tion, a new dog or child). Training is the first step in solving psychological bird is accepting food in a bowl placed on the outside feather picking, with correction of any dietary defi- of the enclosure, it should be made to eat a portion of ciencies being a critical part of the therapy. With a perch stand that feather pick often consume pin feathers as if placed near the enclosure door, the bird should be they are attracted to the taste of blood. A craving for taught the “come” command while the trainer holds the minerals, protein and fat of mature feathers may the food for several minutes. Birds given a balanced eral times a day, the bird will gradually learn to perch diet tend to feather pick less and spend less time outside the enclosure and can then be moved to other chewing plants and perches. Once feather A bird that refuses to go back into its enclosure may picking is established, training may decrease the be trained in the same manner by placing food in the severity of the feather picking but will rarely stop the enclosure for 15 minutes. Favoring One Person A bird that has psychogenic polydipsia may respond A bird that fiercely favors one person should be given to a similar behavioral modification program. Con- the basic training, and when the training is finished, sumption of water is restricted to two ten-minute several other people should become involved in giv- periods a day. These birds should be examined for ing the commands and continuing the training inter- possible disease. Sexual stimulation such as stroking, playing with favorite toys and hiding in dark places should Support Groups be avoided (Figure 4. When other people are pre- Veterinarians, bird trainers, behaviorists and bird sent, the bird should be kept away from areas it clubs have begun to offer group support for preven- wants to defend, such as shoulders and its enclosure. Lorenz K: Studies in Animal and Hu- lels with children’s monologue rots (Amazona albifrons) Bird Behav tree Sparrows. Assoc Kingdom Mag, New York Zoological in the development and retention of the Smokey Mountain Cage Bird So- Avian Vet Newsletter 5(3): 1984. Ann Appl Biol 48:409-414, human and parrot phonation: Acous- in great tit (Parus major) J Comp 1960. Detailed informa- tion is available only for the chicken, which serves as the model for studying the development of bursa- and thymus-derived lymphocytes. Conclusions concern- ing the immune system of other avian species from information derived from the chicken may or may not be valid. Initial comparisons among the immune sys- 5 tems of chickens, ducks and geese indicate substan- tial similarities. The strength and functionality of the defense system is genetically determined, and in free-ranging birds is based on natural selection. This inbreed- ing may weaken the immune system and cause these birds to be more susceptible to disease than their free-ranging relatives (Figure 5. The purpose of the defense system is not only to Helga Gerlach protect the individual against invasive organisms, but also to eliminate abnormal body cells. These include cells with minor structural or antigenic de- viations, such as old cells, virus-infected cells and transformed (cancer) cells. The defense system also functions in the recognition of foreign cells, as is observed in graft rejection phenomena. For this sys- tem to function properly, it is mandatory that the body be able to distinguish between normal body cells (self antigens) and those antigens that are un- like self (foreign antigens). If the body becomes intol- erant of its own cells, then an autoimmune disease occurs. The defense system consists of several integrated components: nonspecific defense, and specific de- fense, which includes the humoral immune system, cell-mediated immune system and tolerance. Cockatiels with color mutations have a reduced life-span and increased infectious disease problems. Few color mutation cockatiels approach the 15- to 20-year longevity that their wild-type relatives enjoy. Each component of the defense system is intricately connected to the other components through the inter- action of cells and hormone-like mediators or secre- tions. These mediators are responsible for activating or suppressing other components of the system, keeping the defenses in proper balance. It is essential for the avian clinician to have an understanding of the importance and interaction of the important com- ponents of the defense system. This is The native flora of the skin is specified and regulated achieved by adhesion of bacteria to the epithelial cell, by factors such as desquamation, desiccation and a eg, by pili or fimbria, by production of bacteriocins relatively low pH. This flora is species-specific, and its composition is governed by the prevailing physical and chemical conditions in the lumen. The acquired flora takes up the available space, occupies receptors and acts competitively against invaders by various mechanisms such as inhibitory metabolic products, bacteriocins and pro- duction of a low pH environment. A practical example of the protective nature of resident bacteria in the gastrointestinal tract is the inhibition and expulsion of Enterobacteriaceae by lactobacilli. This inhibition is particularly important in birds in which Entero- bacteriaceae are not considered to be normal compo- nents of the intestinal flora. The natural develop- ment of the immune system also depends on co ntinuo us antige nic stimulation by the autochthonous flora. Mucosa-associated lymphatic tissue forms the so-called lymphoepithelial system, which appears to function by capturing and process- ing antigens from the mucosal surface. The mucosa of the respiratory, urinary and reproduc- tive tracts of birds is similarly colonized by specific flora whose compositions are relatively unknown; however, thus far it has been shown that none of these mucosal surfaces normally contain Enterobac- teriaceae.