CH 40 Infections: Viral & Rickettsial

Question 1

Polio

Answer 1

asymptomatic in 90-95%, caused by underlying immune deficiency or partial immunization

Question 2

Polio signs and symptoms

Answer 2

fever, myalgia, sore throat, headache for 2-6 days that progress to loss of reflexes and flaccid paralysis with sensation remaining intact. May have symptom free days followed by recurrent fever and signs of aseptic meningitis (HA, stiff neck,nuchal rigidity, nausea). Mild cases resolve completely. Paralysis is usually asymmetrical and usually more proximal. Bulbar involvement affects speech, swallowing, cardiac function, and may cause death. Bladder distention and marked constipation. Paralysis resolves when temp normalizes. improvement of muscle paralysis within 6 months

Question 3

Polio labs

Answer 3

CSF may show lymphocytic pleocytosis and a normal glucose with mildly elevated protein. Easy to differentiate in cell culture. more easily isolated in throat and stool following infection. use PCR

Question 4

Polio Complications

Answer 4

result of permanent destruction of anterior horn cells and paralysis. Resp (usually causes death), pharyngeal, bladder, bowel malfunction are most critical. Limbs injured during infection (from IM injection, trauma, excessive prior use) are more likely to have provocation paralysis

Question 5

encephalitis

Answer 5

common severe manifestation of many infections spread by insects.

Question 6

encephalitis signs and symptoms/diagnosis

Answer 6

fever and headache, diagnosed made clinically during recognized outbreaks and is confirmed with by virus specific serology

Question 7

encephalitis prevention

Answer 7

control of mosquito vectors and precautions with proper clothing and insect repellents to minimize bites and tick bites.. Exclude herpes encephalitis

Question 8

West nile virus

Answer 8

flavivirus, most important arbovirus infection in US.

Question 9

West nile virus

Answer 9

fever, headache, retroorbital pain, nausea, vomiting, lymphadenopathy and a maculopapular rash. More common in those over 50 but may develop in kids.

Question 10

West nile virus complications

Answer 10

meningitis or encephalitis.

Question 11

West nile encephalitis in kids (signs and symptoms)

Answer 11

polio like acute flaccid paralysis, movement disorders (parkinsonism, tremor, and myoclonus), brainstem symptoms, polyneuropathy, optic neuritis, muscle weakness, facial palsy, and hyporeflexia. slow recovery

Question 12

West nile encephalitis diagnosis

Answer 12

best made by detecting IgM antibody (enzyme immunoassay) to the virus in CSF. Will present by 5-6 days after onset using PCR. Antibody rise in serum is also used.

Question 13

West nile encephalitis treatment

Answer 13

supportive, antivirals and immunoglobulins are being studied. be careful as it can be spread by donated organs, blood, breast milk, and across placenta

Question 14

Colorado tick fever

Answer 14

endemic in high plains and mountains of central and northern rocky mountains and northern pacific coast of US. Reservoirs are squirrels and chipmunks

Question 15

Colorado tick fever signs and symptoms

Answer 15

incubation period of 3- 4 days (14 day max). fever begins suddenly with chills, lethargy, headache, ocular pain, myalgia, abdominal pain, nausea and vomiting. may have conjunctivitis. lasts 7-10 days and several patients have biphasic fever (afebrile days in midst of illness)

Question 16

Colorado tick fever labs

Answer 16

leukopenia, decreased platelets. tested with ELISA using seroconversion. Fluorescent antibody staining will detect virus infected erythrocytes during illness and for weeks after recovery.

Question 17

Colorado tick fever complications

Answer 17

Meningoencephalitis , cardiac and pulmonary issues

Question 18

Colorado tick fever prevention and treatment

Answer 18

avoid endemic areas and avoid tick bites. Supportive therapy. Don’s use pain meds that modify platelet function

Question 19

mumps

Answer 19

paramyxovirus spread by resp route and attacks all unprotected children. Infectious from 2 days prior to and 5 days after onset of parotitis. Incubation of- days

Question 20

mumps signs and symptoms

Answer 20

fever, severe HA, aches, anorexia, parotid gland swelling, Salivary gland disease (parotid stimulation with sour foods is painful and orifice of Stensen duct may be red and swollen, secretions may be yellow), meningoencephalitis, pancreatitis (epigastric abdominal pain), orchitis, oophoritis (usually unilateral tenderness and swelling), thyroiditis, mastitis, arthritis, presternal edema

Question 21

mumps labs

Answer 21

leukocyte is normal, mildly elevated protein, slightly decreased glucose. Viral culture or PCR test of saliva, throat, urine, spinal fluid may be positive for one week after onset. Diagnosis with positive IgM antibody and ELISA

Question 22

mumps complications

Answer 22

nerve deafness (usually unilateral) resulting in inability to hear high tones. Adueductal stenosis and hydrocephalus, myocarditis, transverse myelitis, facial paralysis

Question 23

mumps treatment

Answer 23

supportive, includes provision of fluids, analgesics, scrotal support for orchitis (corticosteroids)

Question 24

rabies

Answer 24

acute progressive CNS viral zoonotic infection. Dogs and cats most responsible. History of animal bite 10 days to 1 year previously

Question 25

rabies signs and symptoms

Answer 25

most occur 3-12 weeks of exposure and may have vague symptoms. Paresthesia at bite site, non specific anxiety, excitabilty, or depression follows then muscle spasms, drooling, hydrophobia, delerium, lethargy. Pharygeal spasms from swallowing or air blown in the face. Seizures, fever, cranial nerve palsies, coma, and death follow within 7-14 days

Question 26

rabies labs

Answer 26

leukocytosis, CSF usually normal. Cerebral imaging ang EEG not diagnostic. Test brain tissue of animal for antigen. Excreted in saliva of infected humans.

Question 27

rabies prevention

Answer 27

vaccination, rabies immunoglobulin and diploid cell vaccine

Question 28

rabies treatment

Answer 28

survival is rare, early diagnosis is important for survival

Question 29

Rocky Mountain spotted fever

Answer 29

most severe Rickettsia rickettsii. reservoirs: dogs and rodents and large mammals.

Question 30

Rocky Mountain spotted fever signs and symptoms

Answer 30

incubation period 3-12 days, high fever, abrupt onset, myalgia, severe and persistent HA (retroorbital), toxicity, photophobia, vomiting, abdominal pain, and diarrhea. rash on palms, soles, and extremities (face is spared).

Question 31

Rocky Mountain spotted fever labs

Answer 31

thrombocytopenia, hyponatremia, early mild leukopenia, proteinuria, mildly abnormal liver function tests, hypoalbuminemia, hematuria, CFS pleocytosis. Diagnosed with indirect fluorescent or latex agglutination antibody methods

Question 32

Rocky Mountain spotted fever treatment

Answer 32

must be started early. Doxycycline for 10 days

Question 33

Rocky Mountain spotted fever complications

Answer 33

death resulting from vasculitis, persistent neuro deficits

Question 34

Q Fever

Answer 34

coxiella burnetil is transmitted by inhalation. Sources: birth tissues and excreta of domestic animals and some rodents

Question 35

Q Fever signs and symptoms

Answer 35

self limited flu like syndrome (chills, fevere, severe HA, abrupt onset myalgia), abdominal pain, vomiting, chest pain, dry cough, hepatosplenomegaly

Question 36

Q Fever labs

Answer 36

leukopenia with left shift, elevated aminotransferase and y glutamyl transferase. Diagnosis with four fold rise or single high titer in ELISA.

Question 37

Q Fever imaging

Answer 37

segemental infiltrates if there is pneumonitis

Question 38

Q Fever treatment

Answer 38

lasts 1-2 weeks without therapy. treat with doxycyline for 10-4 days. Quinolones also effective.

Question 39

Q Fever complications

Answer 39

chronic dz: myocarditis, grabulomatous hepatitis, meningoencephalits, endocarditis