Sai Sajja
Also the AIDS patient can suffer from acute appendicitis.
Human immunodeficiency virus (HIV) infection and its inevitable con- sequence of acquired immunodeficiency syndrome (AIDS) is a major public health problem worldwide that has affected the way surgery and medicine are practiced.
With the advances in medical treatment, people infected with HIV are living longer so it is likely that most of you, wherever you practice, will encounter and treat patients with HIV/AIDS. While the general principles of emergency abdominal surgery described elsewhere in this book are relevant to the HIV patient, we will highlight below what is unique to this population.
Natural History
This disease presents a spectrum ranging from asymptomatic HIV infection to advanced AIDS, including its associated opportunistic infections.
Depending on the CD4+ count HIV disease is categorized as:
Early stage (CD4+ count >500 cells/µl)
Mid stage (CD4+ count 200–499 cells/µl)
Advanced (CD4+ count 50–200 cells/µl)
Terminal (CD4+ count <50 cells/µl).
A CD4+ count of <200cells/µl now is defined as AIDS irrespective of the presence of symptoms or other illnesses.A long list of opportunistic infections and cancers, when present, place the HIV-infected patient in the category of AIDS.
* Why a separate chapter on HIV/AIDS? We’re sure we are not alone in deploring the current trend in making some diseases (AIDS and breast cancer being the most notable) more
“fashionable”, and their sufferers more worthy of support and sympathy than regular patients. This chapter is emphatically not an addition to this regrettable development, but an acknowledgement that these patients and their illness may be different in a surgically relevant way (The Editors).
Abdominal Pain
Abdominal pain and non-specific gastrointestinal complaints are very com- mon in patients with HIV/AIDS (> Fig. 33.1). Clinical evaluation is difficult as many patients suffer from chronic abdominal symptoms and,for the physician encounter- ing the patient for the first time, what may be the baseline status for the patient may appear very abnormal. Also the list of differential diagnoses is much larger in this population.White blood cell count,which is very valuable in the normal population, is not reliable because of pre-existing leukopenia. Patients often have coexisting infections of the central nervous system, which makes evaluation of the abdominal pain difficult.Anti-viral medications frequently cause chronic abdominal symptoms as well as acute pancreatitis. A thorough history, including the stage of the HIV disease,the presence of opportunistic infections and the anti-retroviral therapy,and a careful physical examination along with an erect chest X-ray and abdominal X-rays and routine laboratory tests, including serum amylase and lipase, form the basis on which further management is planned.
When the initial examination is inconclusive, serial examinations often yield valuable information. In the absence of clinical peritonitis, free intra-peritoneal air and exsanguinating hemorrhage, CT scan of the abdomen and pelvis is an indis- pensable investigation in AIDS patients. It often identifies non-surgical pathology and avoids a non-therapeutic laparotomy.> Table 33.1 shows causes of abdominal pain in HIV/AIDS and > Fig. 33.2 the suggested clinical approach. (Note that the algorithm in that figure differs from the management of a non-HIV/AIDS patient
Fig. 33.1. “Is it appendicitis or CMV colitis again?”
Table 33.1. HIV-related and HIV-unrelated causes of abdominal pain according to the need for source control
HIV-related conditions Non-HIV-related conditions
Surgical CMV bowel perforation Appendicitis procedure CMV-related toxic megacolon Cholecystitis usually Acalculous cholecystitis Secondary peritonitis
indicated Kaposi sarcoma Intra-abdominal
Lymphoma with abscesses
bowel perforation Intestinal ischemia
Splenic abscess Trauma
Usually Uncomplicated CMV Organomegaly
conservative infection Constipation
management Mycobacterium Uncomplicated
avium complex peptic ulcer disease
Mycobacterium Uncomplicated
tuberculosis pelvic inflammatoy
Pancreatitis: infectious disease (CMV, MAC),
drug-induced (pentamidine, dideoxyinosine, trimethoprim- sulphamethaxazole)
CMV cytomegalovirus; MAC Mycobacterium avium complex.
really only in the early and uniform use of CT scanning in patients not scheduled for early surgery).
Specific Conditions
Acute appendicitis. That a patient suffers from AIDS does not mean that he cannot develop acute appendicitis and, in fact, the incidence of appendicitis in the HIV population appears to be higher than in the general population. While some patients present with typical symptoms and localizing signs in the right lower quadrant, often the presentation is atypical: diarrhea and vomiting are seen fre- quently while fever and leukocytosis are not very reliable. CT scan is the diagnostic imaging study of choice when the presentation is atypical. Interestingly, CMV (cytomegalovirus) infection and Kaposi sarcoma of the base of the appendix have been reported to cause appendicitis.The operative and post-operative management are similar to those in the non-HIV population (> Chap. 28).
Cytomegalovirus. In the AIDS patient, CMV is found in every organ system in the body, is the most common opportunistic infection of the gastrointestinal tract, and often involves the colon – causing fever, diarrhea and abdominal pain. CMV infects endothelial cells, leading to thrombosis of the sub-mucosal blood vessels which results in mucosal ischemia, ulceration, hemorrhage, perforation and toxic megacolon. Diagnosis is established by colonoscopy and biopsy, which shows characteristic intra-nuclear inclusion bodies. CT scan findings of thickening of bowel wall and mural ulceration are non-specific. Once the diagnosis is established, treatment with ganciclovir or foscarnet is started. It is very important to keep these patients under close observation while they are on medical therapy,to identify early the development of complications.Despite aggressive medical management some patients develop perforation, toxic megacolon and hemorrhage – complications that require urgent surgical intervention – following adequate fluid resuscitation and institution of broad-spectrum antibiotic therapy.The perforations related to CMV appear punctate when viewed from the serosal surface. Resection of the
Fig. 33.2. An approach to abdominal pain in AIDS patients
involved segment of bowel and formation of a colostomy or ileostomy – rather than primary anastomosis – is the treatment of choice. Toxic megacolon with impending perforation is best managed with a sub-total colectomy and ileostomy.
Acute cholecystitis. Right upper quadrant abdominal pain associated with fever, nausea and vomiting is a common complaint in patients with HIV/AIDS.
While the cause of this pain may be due to hepatomegaly associated with granulo- matous infiltration or colitis, the possibility of biliary pathology needs to be inves- tigated. Although gallstones are present in many HIV/AIDS patients undergoing cholecystectomy they are also believed to have a relatively high incidence of acalculous cholecystitis. CMV and Cryptosporidium are the commonest oppor- tunistic micro-organisms isolated from the affected gallbladders: overwhelming growth of the pathogens seems to cause inflammation and functional obstruction, unlike the combination of hypotension, ischemia and sepsis that is believed to be the cause of acalculous cholecystitis in the non-HIV,critically ill patient.Ultrasound is the initial imaging study of choice: gallstones, size of the common bile duct, gall- bladder wall thickness, pericholecystic fluid and intramural air can be demonstrat- ed. CT scan and HIDA scan (radioisotope hepatic iminodiacetic acid) are useful when the sonogram is inconclusive. As the pathogenesis of acalculous cholecystitis may not involve cystic duct obstruction, the HIDA scan may demonstrate gallblad- der filling. Once the diagnosis is established, depending on the overall condition of the patient, surgical intervention is recommended. Laparoscopic cholecystectomy can be safely performed, as experimental observations have not substantiated the concerns of aerosolization of HIV virus in the laparoscopy gas. To prevent blood spray during retrieval of the gallbladder, the pneumoperitoneum must be evacuat- ed first. The routine use of specimen bags is recommended to prevent the acciden- tal spillage of infected contents. The relatively high morbidity and mortality of cholecystectomy in these patients reflects the fact that acalculous cholecystitis oc- curs in the more advanced stages of AIDS.
Splenic abscess. Splenic abscess is more common in patients with HIV/AIDS.
Metastatic spread from other infections, secondary infection of a splenic infarct and contiguous spread from an adjacent organ, are the possible mechanisms of its development. CT scan or ultrasound establishes the diagnosis. In the absence of loculations, percutaneous CT-guided drainage of splenic abscess has a reasonable success rate. Splenectomy is the definitive treatment when radiological features do not favor percutaneous drainage or to salvage a failed radiological intervention.
Perianal sepsis. Acute anorectal conditions are discussed in > Chap. 29 but AIDS patients are different. Anorectal pathology is very prevalent in the HIV/AIDS population,especially in those who practice anal-receptive intercourse.While being susceptible to anorectal problems of the general population, HIV/AIDS patients are additionally prone to a variety of opportunistic infections like CMV, herpes, and benign and malignant neoplasms in the perianal area. Careful inspection of the
perianal area,gentle digital rectal examination and a proctoscopic visualization will identify the perianal condition. Examination under anesthesia is an essential part of evaluation before definitive surgical therapy. As in the non-HIV population, perianal sepsis in this population could result from cryptoglandular disease or, by contrast, be associated with HIV-related anorectal ulcers or result from secondary infection of anal proliferative lesions. The abscesses associated with HIV-related anorectal ulcers tend to be very deep – transgressing the sphincter planes – with variable destruction of the sphincter mechanism. Surgical intervention is usually necessary: abscesses should be liberally drained and specimens should be obtained for acid-fast staining and culture. Biopsy for histology is done if underlying malig- nancy is suspected. The principles of treatment are similar to the management of perianal sepsis in Crohn’s disease – it has to be conservative. Damage to the sphinc- ters is avoided and non-cutting setons and drains are utilized liberally. Delayed wound healing is a major concern with CD4+ cell count of less than 50/µl being a predictor of delayed wound healing.
Remember:
The general principles of surgical care described in this book are applicable to the HIV/AIDS patients; however, a thorough understanding of the natural history and the spectrum of HIV disease is essential. The pathology may or may not be related to their HIV status
Abdominal complaints are extremely common in the HIV population and clinical evaluation is often difficult. Serial clinical examination and frequent use of CT scan are essential to prevent non-therapeutic interventions
Early diagnosis and prompt intervention are essential for non-HIV-related surgical pathology like acute appendicitis and cholecystitis. Surgical inter- vention is also essential for complications of opportunistic infections like CMV perforation. The morbidity and mortality for surgical procedures depends on the stage of the HIV disease and the nature of pathology.
Surgical interventions should not be denied to this population because of the risk of occupational transmission and the fear of high complication rates.
Relief of symptoms and improvement in quality of life are the chief con- siderations.
