Question

A 40-year-old male called 911 stating that he was having difficulty breathing and felt too nauseous to drive himself to the hospital. He said he had type I diabetes and had not been able to afford insulin on a consistent basis, especially over the past week, since he lost his job. Fortunately, the emergency medical team promptly got to the patient and took him to the hospital. His blood work revealed an exceedingly high blood glucose level, a finding consistent with the fact that the body relies on insulin to get glucose into cells. The patient was diagnosed as suffering from ketoacidosis. This is a metabolic state in which the body perceives that it is starving for glucose and so switches to mainly catabolizing fats. In ketoacidosis, ketones, which are by-products of fat catabolism, rapidly build up in the body and dangerously lower the blood’s pH level. After stabilizing the patient, a thorough physical examination was performed. Upon physical examination, the physician noticed the man had an infected ulcer on his foot. A bacterial specimen was collected and analysis showed Gram-positive rods that form endospores. The doctor said it was fortunate that the man sought medical assistance, because he could have gone into a coma and died from ketoacidosis. Also, he told the patient that if ketoacidosis had not killed him, the foot wound could have. The ulcer was infected with an anaerobic bacterium, Clostridium perfringens, which causes gas gangrene. The patient stated that he often had slow-healing sores on his feet and asked if it was something to be concerned about. The doctor explained that people who have diabetes and do not consistently regulate their blood glucose often suffer from a number of complications, including circulatory system vessel damage. When blood vessels are damaged, blood delivery to the tissues is decreased, which can affect healing. This pathology is particularly common in the extremities, and especially the feet. Follow-up care for all wounds is important to prevent future infections with dangerous bacteria like C. perfringens. Fortunately, the patient’s infection was localized and readily responded to basic wound care and a regimen of clindamycin and penicillin.

Case-Based Questions 1. Blood work revealed that the patient had high blood glucose levels. However, ketoacidosis results when the body is “starving” for glucose. Why can these two conditions simultaneously exist in a diabetic patient?

2. Why would the body preferentially metabolize fats before metabolizing proteins?

3. Explain why low blood pH, like that seen in ketoacidosis, is potentially deadly.

4. Why are diabetics at risk for wound infections by anaerobic bacteria like Clostridium perfringens?

5. Name two biochemical tests that were discussed in this chapter that would most likely be negative for Clostridium perfringens. Explain why.

Answer 1

ANSWER

1. In a diabetic patient both high blood glucose level and

    starving for glucose will occur toghether because.

           * Insulin is a hormone which responsible for the utilization

             of glucose by the cells in our body by acting on cells of the

             body and also promote glycolysis.

           * In Diabetic patients cells become resistance to the action

             of insulin(type 2) or less insulin production(type 1) which leads

             to lack of availability of glucose in the cells.

          * At the same time level of glucose in the blood will increases

            which result in both high blood glucose level and cells starving of

            glucose.

2. Body preferentially metabolize fat more than protein because

          * Fat molecule contain nine calories per gram so it is a

            high energy source compared to protein and it can act

            as high fuel source in the body compared to proteins.

3. Low pH seen in ketoacidosis because

          * In ketoacidosis excessive breakdown of fat to fatty acids and

             production of ketone bodies will occur this ketone bodies are acids

             so it shows low pH.

          * If diabetic ketoacidosis is not reversed with insulin administration or

             treatment life threatning complications will occur with in few hours

             and lead to death of the patient.

4. Clostridium perfinges act mainly on damages tissues with vascularity

      impaired and low oxygen level.

    * In the case diabetic patient wounds are more likely to angiopathy and

      delayed healing along with pheripheral neuropathies create a environment

      for infection from pathogens like clostridium perfinges.

5.Biochemical tests which may negative to find clostridium perfinges.

      1. Gram staining.

               * Clostridium perfinges is a spore bearing organism so

                  difficult to find them using gram staining.

      2. Aerobic culture.

              * Clostridium perfinges is a anaerobic bacteria so it more

                 likely to negative in aerobic culture medium.

            

     

   

Answer 2

1.  The patient was not taking insulin, which means that the glucose in the bloodstream couldn’t get into the patient’s cells to be catabolized.

2. Fats are highly reduced molecules, and are thus a richer energy source than proteins.

3. Enzymes that are necessary for cells and tissue to function depend on an optimal body pH.

4. C. perfringens colonizes unhealthy tissues that do not receive enough oxygen, and diabetics have difficulty transporting oxygen to body tissues, especially in the extremities.

5. Pos or Neg

1. Gram - positive

2. Catalase - negative

3. Fermentation - positive

4. Durham tube - positive

5. Oxidase - negative