Part 7: Gram-Negative Rods related to Animal Sources

vector-borne

Transmission of infectious diseases involving animal hosts or vectors

zoonotic diseases

Transmission of infectious diseases involving animal hosts or vectors

Aerobic

Oxygen requirement for Brucellae

Brucellae

Obligate intracellular pathogen

Non-motile, non-spore forming

Motility for Brucellae

Brucella melitensis

goats, acute and most severe infections in humans

Brucella suis

swine, chronic infections

Brucella abortus

cattle

Brucella canis

dogs

Erythritol

a growth factor for Brucellae present in the placentas and fetal membranes of cattle, swine, sheep, and goats

No

Is there erythritol in human placenta?

1 to 4 weeks

Incubation period of Brucella

Brucellosis

Disease of Brucella

Brucellosis

undulant fever, Malta fever

Brucellosis

Characterized by malaise, fever, weakness, aches, and sweats

Brucellosis

Enlarged lymph nodes, spleen, and liver

Brucellosis

After the initial infection, a chronic stage may develop

Tetracycline, Rifampcin

Treatment for Brucella

Francisella tularensis

Small, Gram-negative coccobacillus

tularensis (Type A)

most virulent subspecies of Francisella tularensis

tularensis (type A) [most virulent], holarctica (type B), and mediasiatica

Subspecies of Francisella tularensis

enriched media with cysteine

Growth requirement of Francisella tularensis

Francisella tularensis

Highly infectious (bioterrorism agent)

Vectors, Direct contact with animals, Inhalation, Ingestion (rare)

Transmission of Francisella tularensis

bite of arthropods and flies

one of the transmission of Francisella tularensis

infective aerosols

one of the transmission of Francisella tularensis

Francisella tularensis

most important and resistant to beta-lactam

type A

tularensis

type B

holarctica

Tularemia

Disease of Francisella tularensis

Rabbit fever

Disease of Francisella tularensis

Ulceroglandular tularemia

75% of the cases, ulcerating papule (Francisella tularensis)

Pneumonic tularemia

inhalation of an infective aerosol, bronchial infection and pneumonitis

Oculoglandular tularemia

a droplet touches the conjunctiva of the eye, yellowish granulomatous lesions on the eyelids

Glandular tularemia

no ulceration, only lymph nodes are affected

Typhoidal tularemia

septicemia

Streptomycin, gentamicin

Treatment for Streptomycin or gentamicin

Yersinia pestis

Gram-negative rod that exhibits striking bipolar staining with special stains such as Wright, Giemsa, Wayson, or methylene blue

Nonmotile

Motility of Yersinia pestis?

bipolar staining

Yersinia pestis - Gram-negative rod that exhibits striking ______ with special stains such as Wright, Giemsa, Wayson, or methylene blue

28°C

Yersinia pestis - Growth is more rapid at ______

Yersinia pestis

A potential biological warfare agent – low ID 50

Yersinia pestis

Looks like a safety pin or hair pin wherein the center appears to be clear

V and W antigens

allow the microorganism to survive and grow intracellularly (Yersinia pestis)

pPCP1 plasmid

temperature dependent plasmid

pPCP1 plasmid

20 – 28 deg C (temperature prevailing on the flea) – activity is coagulase; 35 to 37 deg C – fibrinolytic

pFra/pMT plasmid

encodes the capsular protein (fraction F1) – required for the organism to survive in the flea

Plague "Black death"

Disease of Yersinia pestis

2 – 7 days

incubation period of Bubonic plague

Bubonic plague

Sudden onset of high fever and lymphadenopathy

enlarged lymph nodes (buboes) in the neck, groin, or axilla

bite site of Bubonic plague

Bubonic plague

Majority of the cases of plague

Septicemic plague

There is a sudden onset of high fever, chills, and weakness

Septicemic plague

Disease progression may lead to septic shock with associated disseminated intravascular coagulation (DIC), hypotension (septic shock), altered mental status, and renal and cardiac failure

Primary Pneumonic plague

Acquired by direct inhalation of organisms into the lungs.

Primary Pneumonic plague

Characterized by chest pain, cough, hemoptysis, and severe respiratory distress.

Secondary Pneumonic Plague

A complication in approximately 10% of patients with bubonic plague

LPS

endotoxin (Yersinia pestis)

Streptomycin

Drug of Choice of Yersinia pestis

Yersinia enterocolitica

typically causes enterocolitis and early symptoms include fever, abdominal pain, and diarrhea

Yersinia enterocolitica

grows best and motile at 25 deg C, but not at 37 deg C

Yersinia enterocolitica

may cause mild diarrhea that is usually self-limiting

Yersinia pseudotuberculosis

presents clinically as mesenteric adenitis, an acute appendicitis-like syndrome

Yersinia pseudotuberculosis

grows best and motile at 25 deg C, but not at 37 deg C

Yersinia pseudotuberculosis

may cause mild diarrhea that is usually self-limiting

Pasteurella multocida

Nonmotile, Gram-negative coccobacilli with a bipolar appearance

Pasteurella multocida

Transmitted by bites and scratches from cats and dogs

Pasteurella multocida

Clinical presentation:
- Acute onset of redness, swelling, and pain
- Regional lymphadenopathy and low-grade fever

Penicillin G

Drug of choice of Pasteurella multocida

Bartonella

Intracellular, Gram-negative rods

Bartonella

Pleomorphic, slow growing

Bartonella

Difficult to isolate in the laboratory

Bartonella

They can be seen using Warthin-Starry silver impregnation stain (small, black, curved organism either as a single of clusters of organisms)

Bartonella bacilliformis

Vector: Sandfly

Bartonella bacilliformis

The organism produces deformin to promote deformity of RBC cell membranes, and flagella to invade red blood cells.

Ciprofloxacin, doxycycline, macrolides, or sulfamethoxazole-trimethoprim given for at least 10 days

Treatment of Bartonella bacilliformis

deformin

The organism produces _______ to promote deformity of RBC cell membranes, and flagella to invade red blood cells.

Oroya fever

a serious infectious anemia

Verruga peruana

eruptive stage (successive crops appear on the skin), may last for 1 year

Bartonella henselae

Transmission: Contact with infected cats through skin lesions

Cat-scratch disease

Disease of Bartonella henselae

Cat-scratch disease

A primary skin lesion (papule or pustule) develops at the site

Cat-scratch disease

A primary skin lesion (papule or pustule) develops at the site

Cat-scratch disease

Common in immunocompetent individuals

Bacillary angiomatosis

A disease predominantly of immunosuppressed individuals (AIDS patients)

Bacillary angiomatosis

It presents as an enlarging red (cranberry-like) papule, often with surrounding scale and erythema

oral erythromycin

Treatment for Bacillary angiomatosis

Peliosis hepatis (Bacillary peliosis)

lesions occur primarily in the liver and spleen.

doxycycline plus gentamicin

Treatment for Bacillary angiomatosis

Humans and body louse

Reservoir of Bartonella quintana

Trench fever

Disease of Bartonella quintana

Bartonella quintana

Characterized by sudden onset of fever accompanied by headache, malaise, restlessness, and shin pain

Bartonella quintana

Five-day fever

Bartonella quintana

More frequently seen at present as a cause of endocarditis and bacteremia in homeless individuals

Trench fever

a common disease during the first world war