Reduction of mortality in chloramphenicol-treated severe typhoid fever by high-dose dexamethasone

Presence of endotoxemia and its relationship to liver dysfunction in patients with typhoid fever

Twenty-one patients with typhoid fever were studied to evaluate the presence of endotoxin in peripheral blood and its relationship to the incidence and features of hepatic dysfunction which may occur during this disease. The limulus test for endotoxin was positive in the plasma samples of all patients prior to treatment. Liver dysfunction, as assessed by fasting and postprandial serum bile acid levels and by standard biochemical tests, occurred in 90% of patients. In seven, the injury was purely cholestatic (elevation of postprandial serum bile acid levels, alone); in 12, it was of mixed cholestatic-hepatocellular type (elevation of both serum bile acids and aminotransferase levels). After recovering, the limulus test was negative and liver function tests returned to normal values in all patients. The results demonstrate that endotoxemia is present in patients with typhoid fever. In addition, since endotoxin can impair bile secretion, our results suggest that endotoxin may have a pathogenetic role in the development of liver injury during typhoid fever.

Gastrointestinal zoonoses

Infectious gastrointestinal diseases affect man and animals throughout the world. Certain etiologic agents (for example, Salmonella spp., Campylobacter jejuni, Yersinia enterocolitica, Cryptosporidia, Strongyloides stercoralis, Echinococcus granulosa) seem to have the potential to be transmitted from pets to people, causing severe disease in the latter. Other agents seem unlikely to be transmitted but may have the potential to be zoonoses. This article discusses proved, suspected, and possible zoonotic agents that may originate from the gastrointestinal tract of dogs and cats.

New developments in infectious diarrhea

The past decade has produced exciting advances in our knowledge of infectious diarrhea. The list of potential enteric pathogens continues to grow with both the identification of new organisms, e.g., E. coli serotype O157:H7, and the recognition that previously characterized microorganisms, e.g., M. avium-intracellulare, can also cause gastrointestinal disease in immunosuppressed patients. Multiple investigations have led to a greater understanding of the epidemiology and clinical features of these illnesses. Application of modern biological techniques has yielded a number of diagnostic assays that are just now becoming clinically relevant. New drugs and treatment modalities for enteric infections have been developed and are now being evaluated in clinical trials. Despite these advancements, however, many questions still remain unanswered. For example, the etiology of the debilitating diarrhea in AIDS patients in whom no known intestinal pathogen can be identified remains unknown. The mechanism of diarrhea due to Cryptosporidium, Isospora, and Giardia remains elusive. And last, will new intestinal vaccines be effective in preventing diarrheal disease? Certainly, the next decade of research in enteric diseases should prove to be even more interesting than the last.

Effect of methylprednisolone on bacterial clearance and endotoxin liberation during experimental sepsis induced by gram-negative bacteria

To determine the effect of methylprednisolone administration on the clearance of bacteremia and the release and clearance of endotoxin during antibiotic therapy of gram-negative bacterial sepsis, Escherichia coli K1 sepsis was induced in paired rabbits. Moxalactam and either methylprednisolone or placebo were administered to infected rabbits 1.5 h after intraperitoneal administration of live bacteria. Serial blood samples were obtained for quantitation of bacteremia and endotoxemia, arterial blood gases, and complete blood count. Arterial blood pressure, heart rate, and core body temperature were also monitored. There were no significant differences between the methylprednisolone-treated and placebo-treated groups in either the levels of bacteremia or endotoxemia or in the physiologic, metabolic, or hematologic parameters that were measured. We conclude that methylprednisolone administration has no acute effect on bacterial clearance or on the kinetics of endotoxin release and clearance during antibiotic therapy of gram-negative bacterial sepsis in this experimental model.

Management of typhoid

Typhoid fever is still a major problem in developing Third World countries where socioeconomic conditions and standards of hygiene are still well below standard. Prophylaxis is far from satisfactory. However, recent developments using live oral vaccines are encouraging. Specific treatment for the disease consists of chloramphenicol or co-trimoxazole; amoxycillin and ampicillin are inferior agents but are of value in several situations because their potential toxic effects are less marked. Most other agents also have drawbacks or are relatively ineffective. In the severely toxic patient, corticosteroids seem to affect prognosis favourably. Of the many other acute complications of typhoid fever, ileal perforation is the most serious; there is still controversy concerning the respective roles of conservative and surgical management, but it is clear that individual cases must be assessed on their merit. Amoxycillin, because it is very rapidly absorbed and produces very high blood concentrations, is probably the best antibiotic for the carrier state.