1. Chapter 5: Infectious and Parasitic Diseases
Med 122

2. This chapter is about
Diseases that are recognized as communicable or transmissible and some diseases of unknown but possibly infectious origin.
The infectious and parasitic diseases are classified by body site and organism.

3. How is this diagnosed?
There are laboratory tests that are used in the Diagnosis and Treatment of Infectious Diseases. This tells you the type of bacteria involved.
Smear and stain examinations
Gram stain
Gram positive and Gram negative organisms
Acid-fast stains are used when bacteria does not stain well with the Gram Stain.
Other staining methods listed on page 71.

4. After the lab test a Dr may order…
Cultures
The rate of growth, atmospheric needs (anaerobic vs aerobic) and nutritional requirements of the bacterium are clues to it’s identity.
Broths, and agar are most commonly used as growth media.
Grouping of the bacteria growth is called a colony.
Other id’s are odor, pigment, shape, size and consistency of the colony.
Sensitivity tests will tell what antibiotic will treat the infection.

5. Serologic Studies Serologic Studies
These blood tests are used to provide a specific diagnosis when attempts to identify an infectious agent are unsuccessful or impractical or when culture techniques are unavailable
Infectious diseases diagnosed by serologic studies are:
Syphilis, rubella, mycoplasma pnueumoniae, Lyme disease and mononucleosis.

6. When a good sputum specimen is collected the gram stain is rapid, simple, and a inexpensive technique to diagnose bacterial pneumonia.
What’s the ICD code for bacterial pneumonia?

7. Microorganisms that Cause Infections
Bacteria- can be gram positive (+) or gram negative (-)
Parasites- these organisms that live in or on another living organism
Fungi- Cause infectious diseases including poisonings, allergies, cutaneous, or mucous membrane infections
Fungi Does not spread from person to person
Virus- infectious microorganism that is much smaller than a bacterium and survives only within a living host cell because it doesn’t have it’s own RNA/DNA
The entire health record must be reviewed to identify the body site, severity, specific organism or parasite, etiology of the infection, and associated signs & symptoms

8. Common Bacteria Gram (+) the organism stain purple
Also depends on shape. They may be in clusters or chains
Rods –
Cocci -
Gram (+) the organism stain purple
Streptococcus
Staphylococcus
Clostridium
Anthrax
Listeria
Lactobacillus
Peptococcus
Gram (–) the organism stain red
Salomonella
Proteus
Shigella
Neisseria
Enterobacteriaceae
Serratia
Common Bacteria

9. Gram staining will tell the shape of the bacterium. Rods vs Cocci
Organism
Cocci in chains
Cocci in clusters
Straight rods
Brick shaped rods
Streptococci
Staphylococci
Salmonella
Clostridium perfringens
Gram staining will tell the shape of the bacterium. Rods vs Cocci

10. Common Parasites and Fungi
Worms are parasites and include tapeworms, flukes, roundworms, pinworms, hookworms, and whipworms.
Candidiasis infection is most common fungi.
Disease may be localized to the mouth, throat, skin, scalp, vagina, fingers, nails, bronchi, lungs, or GI tract.
Common Parasites and Fungi

11. Common Viral Infections
Adenoviridae
Arbovirus
Aseptic meningitis
Cytomegalovirus
Epstein-Barr virus
Hepatitis viruses
Herpes simplex virus
HIV
Influenza virus
Measles
Mumps
Papilloma viruses
Paralytic poliomyelitis
Respiratory syncytial virus
Varicella zoster
Rabies

12. Coding the bugs, sequencing rules
Multiple coding is often necessary to completely describe an infectious condition and the organism that caused it.
Infectious agents are assigned as secondary to describe the causing organism when the organism is not specified in the code title.
Example: UTI due to E. coli
599.0, UTI
041.4, E. coli

13. V09
Code V09 is used as an additional code for infectious conditions to indicate the presence of drug resistance in the infectious organism.
Code assignment should not be based on the laboratory or sensitivity report alone.
The physician should document this in the record.

14. Some Bacteria
Streptococcus (group A) responsible for URI’s spread by droplets or direct contact.
Streptococcus pneumoniae found in the mouth of 10%-40% of people. This bug can also cause lobar pneumonia in adults and sinusitis & otitis media in children and meningitis in elderly people.
S. aureus cause infections involving the skin and subcutaneous tissues, the eye, or ear. Can also cause pneumonia, endocarditis, food poisoning, toxic shock syndrome. Can be transmitted by direct spread or through the bloodstream.

15. Tuberculosis (TB)
TB is highly contagious, an acute or chronic infection caused by Mycobacterium tuberculosis.
It occurs primarily in the lungs, but it can occur in other sites.
A fifth digit is required to identify the method used to establish the diagnosis.

16. Streptococcal (Strep) Sore Throat
ICD-9-CM classifies strep throat to code
No additional code is necessary to identify the organism because it is already included in the title of code
Find in your ICD-9 book now.

17. Septicemia
Septicemia is a bloodstream infection caused by the entry of pathogens into the blood.
Blood cultures are usually positive but can be negative in a patient with the disease.
Septicemia codes include the underlying disease.
Coding guidelines exist for septicemia, septic shock, and SIRS. (what’s SIRS?)

18. Sepsis, see page 77
The terms septic shock, severe sepsis, sepsis and septicemia may be used interchangeably by physicians but they are clinically distinct conditions.
The term sepsis is indexed to code and severe sepsis is indexed to code
Septic shock meets the definition of severe sepsis

19. Coding Sepsis
The “code first” note at subcategory provides instruction that the underlying cause of the sepsis should be coded first.
In the absence of a specified underlying condition, the default first code should be
If documentation is unclear whether the sepsis was present on admission, ask the provider.
The term sepsis or SIRS must be documented to assign a code from subcategory

20. Meningitis
Bacterial meningitis is an inflammation of the meninges and is classified to category 320.
However, Meningococcal meningitis is coded with

21. Childhood Communicable Diseases
Chicken pox (052) or varicella is a common acute and highly contagious infection caused by the herpes virus varicella zoster. Category is subdivided to identify the presence or absence of complications.
Measles (055) is one of the most common illnesses known. Category is subdivided to identify the presence or absence of complications.
Rubella (056), or German measles, is an acute, mildly contagious viral disease.
Category 056 is further subdivided to identify complications.
When rubella is documented as congenital, code should be assigned.

22. Herpes- Contagious stuff!
Herpes zoster (053), or shingles, is a severe infection caused by the varicella zoster virus.
Herpes simplex type 1 & 2 is the gift that keeps on giving!
Herpes simplex 1 is transmitted by oral & respiratory secretions, affecting skin & mucous membranes with cold sores and fever blisters.
Herpes simplex 2 affects primarily the genital area and is transmitted by sexual contact.

23. Hepatitis
Viral hepatitis (070) is an inflammation of the liver caused by a virus.
The five forms of hepatitis include:
Type A- contagious, transmitted by oral-fecal route
Type B- transmitted by direct exchange contaminated blood, human secretions, feces.
Type C- transmitted through blood transfusions. The blood donors do not know they have it.
Type D- found only in patients with acute/chronic episode of hepatitis B
Type E- transmitted enterally (what’s this?)

24. Candidiasis
Candidiasis (112) is a fungal infection caused by the Candida species moniliasis.
The category is further subdivided to identify the specific site affected. This is usually a mild & superficial. Occurs in nail, skin, mucous membranes, vagina, esophagus, and GI tract. Sometimes can enter the bloodstream and invade kidneys, lungs, brain or other major organs.
Neonatal candida monilia infection is excluded from this category and is assigned to

25. STD’s Contagious, spread by sexual contact or intercourse. Include:
Syphilis (090–097)
Gonorrhea (098)
Chlamydia (099.5) with fifth digits identifying specific sites

26. Infectious Gastroenteritis
Caused by a variety of organisms including bacteria, viruses, and parasites.
Some of the symptoms include: severe nausea, vomiting, anorexia, abdominal cramps, fever, malaise, muscle aches, hypokalemia, acidosis.
Several categories are used to classify including 003.0, Salmonella gastroenteritis; 005, Other food poisoning; and 008, Intestinal infections due to other organisms.

27. Noninfectious Gastroenteritis
Gastroenteritis not specified as infectious is assigned to either 558.1, 558.2, 558.3, or
Under code (Allergic gastroenteritis and colitis), there is a note to “use additional code” to identify the type of food allergy (V15.01–V15.05).

28. hiv Presence of HIV in blood indicates HIV infection.
HIV1 infection involves five phases, see pg 80
Health records with diagnostic statements of “suspected,” “likely,” “possible,” or “questionable” HIV should be returned to the physician for clarification.
Patients who are seen for an HIV-related illness will be coded with at least two codes—one for the HIV disease and one for the manifestation.

29. Example Delivery of a male infant in mother with AIDS
647.61, Other specified infectious and parasitic disease in the mother
042, HIV disease
V27.0, Outcome of delivery
If a patient with symptomatic HIV disease or AIDS is admitted for an unrelated disease, such as traumatic injury, the code for the unrelated condition is listed first, followed by the code for the HIV infection.

30. example
Patient was seen by the physician who diagnosed acute appendicitis; patient also has AIDS.
540.9, Acute appendicitis
042, HIV disease

31. Coding hiv
V08, Asymptomatic human immunodeficiency virus infection, indicates that the patient has a virus in the blood but has no symptoms of an HIV-related disease.
042, HIV disease, indicates that the patient has an HIV-related disease.
795.71, Nonspecific serologic evidence of HIV is used for patients with inconclusive HIV test results

32. Coding hiv Code V08 is used as long as the patient is asymptomatic.
Code 042 is used once the patient exhibits HIV-related illnesses even when the patient may be asymptomatic for a period of time (never go back to V08).
Code is used for very limited situations when an HIV test is inconclusive.

33. Hiv testing & counseling
V73.89, Screening test for HIV
V69.8, High risk group
V65.44, HIV counseling

34. V codes
There are several V codes applicable to infectious and parasitic diseases.
These are found on page 83