Lyme Disease Overview and Stages

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Questions and Answers

What is the first-line treatment for Lyme disease in Stage 1?

Amoxicillin for 7 days

IV ceftriaxone for 14 days

Cefuroxime for 10 days

Doxycycline PO for 10 days (correct)

What is the recommended prophylaxis for a tick bite when no symptoms are present?

Doxycycline 200mg once (correct)

Cefuroxime 250mg once

No prophylaxis is needed

Amoxicillin 500mg daily for 3 days

Which treatment is appropriate for a patient under 8 years old diagnosed with Lyme disease?

Ceftriaxone IV for 14 days

Azithromycin for 5 days

Amoxicillin or Cefuroxime (correct)

Doxycycline for 21 days

In which stage of Lyme disease is arthritis usually seen?

Late or severe stage Signup and view all the answers

What is the primary method for removing a tick?

Pulling firmly with tweezers on the mouth part Signup and view all the answers

Which characteristic defines primary syphilis?

Presence of a painless chancre Signup and view all the answers

What is the typical size and appearance of a chancre in primary syphilis?

1-2cm, clean based, punched out with raised edges Signup and view all the answers

How is syphilis primarily transmitted among individuals?

During sexual contact Signup and view all the answers

What is the most common tick-borne disease in the US and Europe?

Lyme disease Signup and view all the answers

Which of the following treatments is considered second line for patients with a penicillin allergy?

Doxycycline Signup and view all the answers

Which of the following genospecies of Borreliella is most common in the USA?

Borrelia burgdorferi Signup and view all the answers

What is a key reason that all cases of syphilis must be reported?

To ensure treatment of affected sexual contacts Signup and view all the answers

What is a distinguishing clinical manifestation of Chancroid compared to syphilis?

Tender, usually unilateral lymphadenopathy Signup and view all the answers

What animal reservoirs are primarily associated with B. burgdorferi transmission?

Mice and deer Signup and view all the answers

During which seasons do most human cases of Lyme disease occur?

Spring and summer Signup and view all the answers

Which causative agent is specifically associated with Chancroid?

Haemophilus ducreyi Signup and view all the answers

What is the recommended follow-up for patients treated for syphilis?

Nontreponemal titers every 3-6 months Signup and view all the answers

How long must ticks typically feed to transmit Lyme disease?

24–36 hours or longer Signup and view all the answers

Which symptom is typically associated with the early localized stage of Lyme disease?

Erythema migrans Signup and view all the answers

How is Malaria primarily transmitted?

The bite of infected female anopheline mosquitoes Signup and view all the answers

Which of the following features is NOT characteristic of the ulcers seen in Chancroid?

Hard, clean base Signup and view all the answers

What percentage of patients with erythema migrans may not have typical skin lesions?

10–20% Signup and view all the answers

Which of the following symptoms is commonly associated with the 'summer flu' experienced in Lyme disease Stage 1?

Myalgias and arthralgias Signup and view all the answers

What is the typical duration recommended for syphilis treatment abstention from sexual activity?

7–10 days Signup and view all the answers

What characterizes gummas in tertiary syphilis?

They appear as non-tender nodular lesions with central punched-out necrosis. Signup and view all the answers

Which of the following options describes the skeletal system involvement in tertiary syphilis?

Leads to destructive bone lesions causing periostitis and myalgia. Signup and view all the answers

What is a typical symptom of gastric involvement in tertiary syphilis?

Early satiety and epigastric pain. Signup and view all the answers

What is the effect of gummatous iritis associated with tertiary syphilis?

Causes small irregular pupils that constrict with accommodation. Signup and view all the answers

Which area is least likely to be affected by gummas in tertiary syphilis?

Heart. Signup and view all the answers

Which of these presentations is commonly associated with respiratory involvement in tertiary syphilis?

Wheezing and respiratory distress due to gummatous lesions. Signup and view all the answers

What type of lesions are primarily associated with late syphilis?

Multiple nodular lesions and solitary gummas. Signup and view all the answers

Which of the following describes the involvement of mucous membranes in tertiary syphilis?

Leukoplakia that is highly destructive to the involved tissue. Signup and view all the answers

What is the primary pathway of infection for Plasmodium falciparum after it is injected by mosquitoes?

It first infects the liver and then red blood cells. Signup and view all the answers

Which of the following is NOT a characteristic symptom associated with malaria caused by Plasmodium falciparum?

Persistent cough and chest pain Signup and view all the answers

Why does Plasmodium falciparum lead to severe disease in young children?

They have less developed antimalarial immunity. Signup and view all the answers

What is the mechanism by which Plasmodium falciparum evades clearance by the spleen?

It mediates the sequestration of infected erythrocytes. Signup and view all the answers

What causes the cyclical pattern of fever in malaria patients?

The release of toxins during the lysis of red blood cells. Signup and view all the answers

What is a major consequence of severe Plasmodium falciparum infection?

Cerebral malaria leading to neurological complications. Signup and view all the answers

In which stage of malaria infection does lysis of red blood cells occur?

After the parasite matures in the liver. Signup and view all the answers

What is the most severe complication as a result of Plasmodium falciparum infection in children?

Cerebral malaria resulting in coma. Signup and view all the answers

Study Notes

Lyme Disease

Most prevalent tick-borne disease in the US and Europe.
Caused by the spirochete Borreliella species.
In the USA, the dominant genospecies is Borrelia burgdorferi; B. garinii and B. afzelii are predominant in Europe and Asia.
Highest incidence reported from the mid-Atlantic, northeastern, and north central regions of the USA.
Primary vectors include Ixodes scapularis (northeast/north central USA), Ixodes pacificus (West Coast USA), and Ixodes ricinus (Europe).
Key animal reservoirs for B. burgdorferi are mice and deer.
Most human infections occur in spring and summer; transmission requires tick attachment for 24–36 hours.

Stages of Lyme Disease

Stage 1 (Early Localized Infection):
- Characterized by erythema migrans, typically beginning 1 week post-tick bite; presents as a flat lesion that expands.
- About 10-20% of patients may not have noticeable skin lesions.
- Patients often experience “summer flu” symptoms: myalgias, arthralgias, headaches, and low-grade fevers.
Stage 2 (Early Disseminated Infection):
- Requires examination of symptoms for appropriate treatment.
Stage 3 (Late or Severe Infection):
- Includes arthritis and central nervous system or cardiac symptoms.
- Treatment includes Doxycycline over 28 days and IV ceftriaxone when indicated.

Syphilis

Caused by Treponema pallidum, primarily transmitted through sexual contact and from mother to fetus.
Men who have sex with men account for nearly half of US syphilis cases.

Clinical Stages of Syphilis

Primary Syphilis:
- Defined by the presence of a painless ulcer called a ‘chancre’ at the inoculation site (1-2 cm).
Tertiary Syphilis:
- Multiple nodular lesions and solitary gummas that can ulcerate; may affect various body systems.
- Gummas lead to destructive conditions in skeletal systems, mucous membranes, respiratory organs, and the GI system.

Tertiary Syphilis Symptoms

Mucous membranes: Gummas, leukoplakia causing tissue destruction.
Skeletal system: Destructive bone lesions with little swelling, causing myalgia and myositis.
Eyes: Iridocyclitis, optic atrophy, and cranial nerve palsies can occur.
Respiratory: Gummatous infiltrates can lead to respiratory distress and wheezing.
GI system: Liver gummas may cause cirrhosis; gastric involvement includes pain and weight loss.

Treatment of Syphilis

Patients with infectious syphilis should avoid sexual activity for 7–10 days post-treatment.
Report all cases to public health authorities; monitor with nontreponemal titers every 3–6 months.

Chancroid

Caused by Haemophilus ducreyi.
Presents as painful genital ulcers with enlarged inguinal lymphadenopathy.

Diagnosis and Treatment of Chancroid

Diagnosis is clinical after ruling out syphilis and HSV; PCR available but rarely used.
Treatment includes Azithromycin or Ceftriaxone.

Comparison: Syphilis vs Chancroid

Pain: Syphilis lesions are painless; chancroid lesions are painful.
Ulcer Characteristics: Syphilis has clean-based, punched-out ulcers; chancroid presents with irregular, undermined ulcers with purulent exudate.
Lymphadenopathy: Syphilis may present with non-tender nodes; chancroid typically shows tender, often unilateral nodes.

Malaria

Causative agent: Plasmodium genus (e.g. P. falciparum, P. vivax).
Transmitted by infected female anopheline mosquitoes.

Pathophysiology of Malaria

Infection begins with mosquitoes injecting Plasmodium into the bloodstream, targeting liver cells.
Mature parasites invade erythrocytes, leading to red blood cell lysis and cyclical fevers.

Symptoms of Malaria

Cyclical fevers consist of cold, hot, and diaphoretic stages; may manifest every 48-72 hours based on Plasmodium type.
Severe symptoms include cerebral malaria, renal failure, and blackwater fever, primarily linked to P. falciparum.

Malaria Impact

High endemic regions develop some immunity; young children remain vulnerable and are often at risk for severe complications like cerebral malaria and anemia.

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Description

This quiz covers the essential facts about Lyme disease, including its causative agents, geographical prevalence, and major vectors. Additionally, it discusses the stages of the disease, focusing on early localized infection and its symptoms. Test your knowledge on this important health issue!