Infectious Diseases

What makes orbital cellulitis different from preseptal cellulitis?

By the presence of pain with extraocular movements, visual changes, proptosis, or ophthalmoplegia

What are the signs of acute infectious lymphangitis?

Signs include red streaks on the skin, swelling, tenderness along lymphatic vessels, and fever.

What are signs of a brain abscess?

Signs include headache, fever, neurological deficits, and seizures in the setting of a sinus infection

What vaccines should HIV patients receive?

HIV patients should receive all routinely recommended vaccines, including pneumococcal, influenza, and hepatitis B vaccines, due to their increased risk of infections.

Are there side effects to the VZV vaccine?

Yes, side effects can include mild fever, rash, and soreness at the injection site. Rarely, more serious reactions may occur.

In managing flu, when is it best to give antivirals?

Antivirals are most effective when given within 48 hours of symptom onset to reduce the duration and severity of the flu.

What signs are present in bacterial conjunctivitis?

Signs of bacterial conjunctivitis include redness, swelling of the conjunctiva, discharge that is often yellow or green, and crusting of the eyelids.

What is the main cause of bacterial conjunctivitis?

Bacterial conjunctivitis is primarily caused by bacterial infections, most commonly by Streptococcus pneumoniae, Staphylococcus aureus, and Haemophilus influenzae.

What is the main cause of meningitis in general population?

Meningitis in the general population is commonly caused by viral infections, but bacterial meningitis can occur due to pathogens such as Neisseria meningitidis and Streptococcus pneumoniae.

What age is GBS the main cause of meningitis?

Group B Streptococcus (GBS) is the main cause of meningitis in newborns and infants, particularly in the first 3 months of life.

Which age group develops Listeria meningitis?

In infants less than 1 month

What antibiotics are used to treat aspiration pneumonia?

Aspiration pneumonia is commonly treated with antibiotics such as ampicillin, amoxicillin-clavulanate, or clindamycin, depending on the patient's clinical condition and risk factors.

Mycoplasma pneumonia is also known as atypical pneumonia. What makes this atypical?

It lacks typical symptoms of bacterial pneumonia, and often presents with a gradual onset of cough and mild fever with headache.

What are the symptoms of babesiosis?

Symptoms of babesiosis include fever, chills, sweats, headache, body aches, loss of appetite, and nausea. Severe cases may lead to hemolytic anemia and organ failure.

What is a good way to remember the organisms of the Viridans strep?

A mnemonic such as "Sally Makes Mouth-Watering And Gorgeous Food" can help recall the organisms: Streptococcus sanguinis, Streptococcus mitis, Streptococcus mutans, Streptococcus anginosus, Streptococcus gordonii, and Streptococcus ferus.

What is seen with pyogenic liver abscess?

Pyogenic liver abscess typically presents with fever, chills, abdominal pain, and may show signs of infection on imaging studies such as ultrasound or CT scans. Liver enzymes will also be elevated

What is required to diagnose infective endocarditis?

Diagnosis of infective endocarditis typically requires a combination of clinical criteria, blood cultures from three different sites to identify the causative organism, and echocardiographic findings to visualize vegetations on heart valves.

What is seen with impetigo?

Red sores, often around the nose and mouth, that can ooze and form honey-colored crusts. It commonly affects children and is caused by bacteria such as Staphylococcus aureus or Streptococcus pyogenes.

What E.coli causes traveler’s diarrhea?

Enterotoxigenic E. coli (ETEC) is the primary strain responsible for traveler's diarrhea, producing toxins that lead to diarrhea and abdominal cramps.

What happens if someone who completed all Hepatitis B vaccines gets exposed to Hepatitis B?

If someone who has completed all Hepatitis B vaccinations is exposed to the virus, they are generally protected due to the immunity developed from the vaccine. However, in certain high-risk situations, a booster dose may be recommended to ensure adequate protection.

What kind of hepatitis can develop from HIV?

Hepatitis A and C, which can co-infect with HIV and lead to more severe liver disease.

In patients with ulcers, what factors can increase the risk of developing osteomyelitis?

Factors such as poor circulation, diabetes, and infection can increase the risk of developing osteomyelitis in patients with ulcers.

For pregnant patients who develop Lyme disease, what antibiotic is given?

Amoxicillin or cefuroxime is prescribed.

What is the post exposure prophylaxis for Hepatitis A?

The post-exposure prophylaxis for Hepatitis A includes administering the Hepatitis A vaccine or immune globulin (IG) within two weeks of exposure.

What antibiotics are used for clenched fist-bite injuries?

Amoxicillin-clavulanate is commonly used.

When exposure of this patient's blood to a control agent does not significantly stimulate interferon-gamma release above baseline, why is that?

This is indicative of a potential anergy or lack of immune response, suggesting that the patient's immune system may not be adequately responding to the infection or antigen.

Is the arthritis from Parvovirus symmetric or asymmetric?

The arthritis associated with Parvovirus is typically symmetric, affecting both sides of the body in a similar pattern.

What kind of edema is seen with chronic lymphedema and what causes it?

Chronic lymphedema typically presents with non-pitting edema, caused by the accumulation of protein-rich lymph fluid due to impaired lymphatic drainage.

What is erythema migrans?

Erythema migrans is a characteristic skin rash associated with Lyme disease, often appearing as a red, circular lesion with a central clearing. It typically develops at the site of a tick bite and can expand over time.

In meningococcal meningitis is suspected, what should be done first: lumbar puncture or antibiotic treatment?

Antibiotic treatment should be initiated immediately, as meningococcal meningitis is a medical emergency that requires prompt intervention.

What antibiotics are given for meningococcal meningitis?

Ceftriaxone or cefotaxime, often combined with vancomycin to cover resistant strains.

What GI symptoms does CMV cause?

Bloody diarrhea, abdominal pain, and esophagitis, particularly in immunocompromised individuals.

What other symptoms does CMV cause?

Fever, fatigue, muscle aches, dyspnea. In severe cases, it may lead to pneumonia and retinitis, particularly in individuals with weakened immune systems.

What TB induration cutoff is used for HIV-positive individuals?

A cutoff of 5 mm or greater is used for HIV-positive individuals to indicate a positive tuberculin skin test (TST) for tuberculosis (TB).

What infections does Vibrio cause?

Gastrointestinal infections, including cholera and gastroenteritis, as well as wound infections and septicemia, particularly in individuals consuming contaminated seafood or exposed to seawater.

What valvular abnormalities are seen with infective endocarditis?

Mitral regurgitation is the most common one

What antibiotics should be given for neutropenic fever?

broad-spectrum antibiotics such as piperacillin-tazobactam or cefepime are recommended.

How can pertussis affect the ribs?

Rib fractures due to severe coughing fits, which lead to increased pressure on the rib cage and potential injury. This leads to sudden onset chest pain and difficulty breathing.

Where is Histoplasmosis most prominent?

Ohio and Mississippi River valleys, where the fungus Histoplasma capsulatum thrives in soil enriched with bird or bat droppings.

Where is Blastomyces most prominent?

Southeastern and south-central United States, particularly in areas near rivers and lakes where the fungus thrives in moist soil.

What bacteria causes oropharyngeal infection and jugular vein thrombosis?

Lemierre's syndrome is caused by the bacterium Fusobacterium necrophorum.

What signs and symptoms are seen with mononucleosis?

Symptoms such as severe fatigue, fever, sore throat, swollen lymph nodes, and an enlarged spleen. It is often caused by the Epstein-Barr virus.

For tetanus prophylaxis, when would someone need to receive tetanus vaccine?

If they have not had a booster in the last 10 years or if they have a dirty or contaminated wound and it has been more than 5 years since their last booster.

For tetanus prophylaxis, when would someone need to get both tetanus vaccine and tetanus Ig?

If they have a dirty or contaminated wound and are unvaccinated, their vaccination history is unknown, or they are not fully vaccinated (all 3 shots)

What factors increase probability of tuberculosis?

chronic cough, fever, weight loss, cavitary upper lobe lesion, lymphadenopathy, and employment history (prison setting)

In someone hospitalized for UTI, what bacteria causes infective endocarditis?

Enterococcus faecalis

When would someone need rabies shot?

When bitten by a potentially symptomatic rabid animal or the animal is not available for testing

What is a main cause of Chlamydia reinfection?

Lack of treatment for partners

If someone is exposed to someone with active HIV, what drugs do they need to be started on?

Post-exposure prophylaxis (PEP) with 3 antiretroviral medications.

What is secondary bacterial pneumonia?

A type of pneumonia that occurs as a complication following a viral infection, typically affecting individuals with weakened immune systems.

What bacteria is the cause of secondary bacterial pneumonia?

Staph aureus

What are features of typhoid fever?

Symptoms include prolonged fever, abdominal pain, headache, and non bloody diarrhea; will also see a salmon colored maculopapular rash

Aside from antibiotics, what other medications can predispose to C. diff?

Medications such as proton pump inhibitors, corticosteroids, and certain chemotherapeutic agents

Despite meningitis vaccination, if someone is exposed to meningitis, what should they be receiving?

Prophylactic antibiotics like rifampin, ceftriaxone, or ciprofloxacin to prevent infection.

In PML, what is shown on CT?

Typically, non-enhancing white matter lesions. These lesions are often located in the frontal and parietal lobes, indicating demyelination.

What is the lesion like in tularemia?

Typically, one painful ulcer at the site of infection, often accompanied by lymphadenopathy.

What are features of ecythema gangrenosum?

Painful, necrotic ulcers with a central eschar and surrounding erythema. It is often associated with Pseudomonas aeruginosa infections, particularly in immunocompromised patients.

What are some predisposing factors to Pneumocystis pneumonia?

Immunocompromised states, such as HIV/AIDS, certain cancers, and prolonged corticosteroid use.

What are concurrent infections that can lead you to think about HIV?

Recurrent pneumonia, oral thrush, and chronic diarrhea.

What is seen with RMSF?

Fever, rash, and a history of tick exposure. It often presents with a petechial rash that begins on the wrists and ankles.

In patients with HIV and have CD4 counts below 50, what should be given as prophylaxis?

Trimethoprim-sulfamethoxazole to prevent Pneumocystis pneumonia.

How would you describe the lesions in bacillary angiomatosis?

Vascular lesions that appear as red, raised nodules or plaques on the skin, often resembling Kaposi's sarcoma. These lesions are caused by Bartonella species and can occur in immunocompromised individuals.

What are symptoms in infective endocarditis?

Fever, heart murmur, petechiae, arthralgia, and splinter hemorrhages. Symptoms may also include fatigue, night sweats, and weight loss.

What antibiotic is best for infective endocarditis while blood cultures are sent?

Empirical treatment with vancomycin.

In someone with septic shock, what will the pulses be like?

Early on, they will be bounding because of the vasodilation and increased cardiac output, but as shock progresses, pulses may become weak and thready due to decreased perfusion.

Which bacteria is partially acid fast, gram-positive, and branching?

Nocardia species

What is best antibiotic for Nocardia?

Trimethoprim-sulfamethoxazole (TMP-SMX)

What is the main feature of bacillary angiomatosis?

The vascular lesions that resemble angiomas, typically caused by Bartonella species and often seen in immunocompromised patients.

What is the risk for contracting community acquired pneumonia for HIV patients?

Increased risk due to compromised immune systems, making them more susceptible to infections, including those that cause pneumonia.

What kind of features are seen with Histoplasmosis infection?

Patients develop a febrile, wasting disorder with prominent pulmonary (dyspnea, cough), mucocutaneous (papules, nodules), and reticuloendothelial (lymphadenopathy, hepatosplenomegaly) manifestations

Patients with disseminated Histoplasmosis get what treatment?

Antifungal medications such as itraconazole or amphotericin B, depending on the severity of the infection.

What are features of cryptococcus meningitis?

Fever, headache, neck stiffness, vomiting, altered mental status, and papilledema. It is often accompanied by a lymphocytic pleocytosis in cerebrospinal fluid.

What are features of disseminated gonococcal infection?

Fever, pustular rash, arthralgia, and septic arthritis. It can also present with purulent arthritis and tenosynovitis.

What bacteria cause prosthetic joint infection?

Staphylococcus aureus, coagulase-negative staphylococci, and Streptococcus species.

What is the difference in onset for prosthetic joint infection between Staphylococcus aureus and coagulase-negative staphylococci?

Staphylococcus aureus typically causes early onset infection within weeks after surgery, while coagulase-negative staphylococci usually lead to late onset infections, occurring months to years later.

What symptoms are seen with dengue?

High fever, severe headache, pain behind the eyes, joint and muscle pain, rash, and mild bleeding. Severe cases can lead to dengue hemorrhagic fever or dengue shock syndrome. Will see leukopenia, thrombocytopenia, and elevated liver enzymes

What are causes of splenic abscess?

Bacterial infections, such as Staphylococcus aureus, or conditions like endocarditis. Splenic abscesses can result from hematogenous spread or direct extension from adjacent organs like the heart.

What is the triad for Trichinella infection?

Fever, myalgia, and periorbital edema.

What does FROM JANE stand for?

Fever

Roth spots

Osler nodes (petechiae)

Murmur

Janeway lesions (painless lesions on the palms and soles)

Anemia

Nail hemorrhage (splinter hemorrhage)

Emboli

If there is substernal chest pain with thrush, what is the treatment?

Antifungal therapy, such as fluconazole.

If an HIV patient is having diarrhea of about 10 days and normal CD4 counts, what is the cause of the diarrhea?

Likely Cryptosporidium

In an immunocompetent patient who has diarrhea for 10-14 days, what is causing it?

Cryptosporidium parvum

What color are the lesions for HHV-8?

Typically red or purple.

Which are the bacteria that cause bloody diarrhea?

Commonly E. coli, Shigella, and Salmonella.

In an HIV patient who injects IV drugs, what is the cause of the infective endocarditis they could develop?

Typically Staphylococcus aureus.

When would isoniazid liver injury start to become a concern?

When it starts to show symptoms of liver injury such as jaundice or elevated liver enzymes.

What kind of bacteria is H. influenzae?

A type of gram-negative coccobacillus that can cause respiratory tract infections and other serious diseases, particularly in unvaccinated children.

How does Entamoeba affect the liver and GI tract?

Can cause amoebic dysentery and liver abscesses, leading to severe gastrointestinal symptoms and potential liver damage.

In a patient discharged with MRSA secondary bacterial pneumonia, what antibiotics are given outpatient?

Outpatient treatment typically includes antibiotics such as trimethoprim-sulfamethoxazole, doxycycline, or clindamycin to target methicillin-resistant Staphylococcus aureus.

In someone who shows symptoms of tetanus, do they need any other confirmatory testing?

Typically, clinical diagnosis is sufficient, as tetanus is diagnosed based on characteristic symptoms and history, without the need for confirmatory laboratory tests.

What antibiotic is used for Mycobacterium avium?

Azithromycin is commonly used for treating Mycobacterium avium infections, often in combination with rifabutin or ethambutol.

For diabetic foot osteomyelitis, when would MRSA coverage be indicated?

MRSA coverage is indicated when there is a history of prior MRSA infection, significant soft tissue infection, or if the patient has risk factors such as recent hospitalization or nursing home residence.

For diabetic foot osteomyelitis, when would Pseudomonas coverage be indicated?

Pseudomonas coverage is indicated in cases of severe infections, especially with prior antibiotic use, or if there are risk factors such as recent hospitalization, presence of ulcers, or warm climates.

Is there prophylaxis needed for contacts of herpes simplex?

Prophylaxis for contacts of herpes simplex is generally not required unless there is a high risk of transmission or recurrent outbreaks in the contact.

What kind of infections can occur in the first month post-organ transplant?

Infections that can occur in the first month post-organ transplant include bacterial infections, viral infections such as cytomegalovirus (CMV), and fungal infections, primarily due to immunosuppression.

What does malignant/necrotizing otitis externa look like?

Malignant or necrotizing otitis externa presents with severe ear pain, swelling of the ear canal, granulation tissue, and purulent discharge. It is caused by Pseudomonas

What is the cause of osteomyelitis for a deep puncture wound?

The cause of osteomyelitis from a deep puncture wound is often due to bacteria, typically Staphylococcus aureus or Pseudomonas aeruginosa, entering the bone through the wound.

What can help decrease the risk of infection in burn patients?

Preventative measures include proper wound care, maintaining a sterile environment, administering prophylactic antibiotics, and early wound excision and grafting

When draining a perirectal abscess, when would patients need to be on systemic antibiotic therapy?

Systemic antibiotic therapy is indicated for patients with signs of systemic infection, such as fever or leukocytosis, or those with underlying health conditions that increase the risk of complications.

What is Ludwig angina?

Ludwig angina is a serious, potentially life-threatening cellulitis of the submandibular space, often resulting from dental infections, which can lead to airway obstruction.