Name That Pathogen!

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birdseed agar is diagnostic for cryptococcus neoformans b/c it is able to metabolize whatever it is in the seed and shows the pigment.

If the dude has cryptococcus in his skin, that's really bad b/c it's usually disseminated from the lungs, right?

:thumbup:

A diagnosis of cryptococcosis of the skin was made. I believe it's inhaled into the lungs, where it can cause a pneumonia. From the lungs, it can hematogenously disseminate to other organs, such as the skin. After interrogating the patient, he revealed that he enjoys feeding the pigeons that frequent the ER.

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:thumbup:

A diagnosis of cryptococcosis of the skin was made. I believe it's inhaled into the lungs, where it can cause a pneumonia. From the lungs, it can hematogenously disseminate to other organs, such as the skin. After interrogating the patient, he revealed that he enjoys feeding the pigeons that frequent the ER.

Thats one interesting ER
 
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Your patient is 4 weeks post allogeneic bone-marrow transplant for non-hodgkins lymphoma. She complains of new-onset blurred vision. Fundoscopic exam shows the following:

61636dlcfun10kk8.jpg
 
Hmm...I'm thinking common infections that come from transplant procedures that effect the retina. No other S & S were mentioned, so I'm going to assume that it's for now asymptomatic, expect for the obvious fundoscopic changes, which look they could be hemorrhages and exudates, and blurred vision.

Rough guess: CMV
TX: IV ganciclovir
 
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Hmm...I'm thinking common infections that come from transplant procedures that effect the retina. No other S & S were mentioned, so I'm going to assume that it's for now asymptomatic, expect for the obvious fundoscopic changes, which look they could be hemorrhages and exudates, and blurred vision.

Rough guess: CMV
TX: IV ganciclovir

CMV retinitis. :thumbup:
 
40 y/o female farmer from the Midwest w/ HIV for 3 years presents to the local ER w/ hemoptysis, fever, chills, night sweats, cough, lymphadenopathy, hepatosplenomegaly, pancytopenia, and weight loss of about 25 lbs. CXR showed patchy infiltrates and nodularity. Given IV levoquin and imipenen. Pt died 10 days post admission, of massive organ failure. On autopsy, a bone marrow aspirate was taken:

art-lab490288.fig1c.jpg
 
40 y/o female farmer from the Midwest w/ HIV for 3 years presents to the local ER w/ hemoptysis, fever, chills, night sweats, cough, lymphadenopathy, hepatosplenomegaly, pancytopenia, and weight loss of about 25 lbs. CXR showed patchy infiltrates and nodularity. Given IV levoquin and imipenen. Pt died 10 days post admission, of massive organ failure. On autopsy, a bone marrow aspirate was taken:

art-lab490288.fig1c.jpg

gonna go with Histoplasma capsulatum

(had to look up the ddx for bone marrow invasive bugs)
 
A young woman presents with a rapidly progressive ascending paralysis. What microbial agent is most likely associated with her condition?


This sounds like an acute inflammatory ascending polyneuropathy (or Guillain-Barre syndrome). While the exact etiology behind this condition is not entirely known, it is often associated with Campylobacter jejuni ingestion. Did this woman recently eat uncooked supermarket chicken?
 
This sounds like an acute inflammatory ascending polyneuropathy (or Guillain-Barre syndrome). While the exact etiology behind this condition is not entirely known, it is often associated with Campylobacter jejuni ingestion. Did this woman recently eat uncooked supermarket chicken?

:thumbup: the patient reported a bout of "stomach flu" a few weeks ago
 
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a young man with sickle cell anemia presents with fever, cough, malaise.

chest x-ray below:


What is the most likely etiologic agent for this man's disease process?

It sounds like the patient is suffering from acute chest syndrome. This may have been brought on by streptococcus pneumoniae sepsis (or other encapsulated bacteria), secondary to autosplenectomy from vaso-occlusive disease.
 
It sounds like the patient is suffering from acute chest syndrome. This may have been brought on by streptococcus pneumoniae sepsis (or other encapsulated bacteria), secondary to autosplenectomy from vaso-occlusive disease.

I was just going for bronchopneumonia (strep pneumoniae), which the pt is more susceptible to as a result of the autosplenectomy.
 
A patient presents with a visibly swollen eye.

mucor3un1.jpg


Examination of the nasal cavity reveals A:
(B) Section of nasal turbinate after excision and (C) marrow section*

*I believe this to be from local marrow, not dissemination
loadbinaryaspxnamelichaub3.jpg



When performing the biopsy, you note the patient's breath has a sweet, fruity odor to it.
 
A patient presents with a visibly swollen eye.

mucor3un1.jpg


Examination of the nasal cavity reveals A:
(B) Section of nasal turbinate after excision and (C) marrow section*

*I believe this to be from local marrow, not dissemination
loadbinaryaspxnamelichaub3.jpg



When performing the biopsy, you note the patient's breath has a sweet, fruity odor to it.

pseudomonas aeruginosa
 
A 50 year old male who recently travelled to Asia presents to the clinic complaining of "numbness" in his toes and fingers and the sensation that it "feels like something is blocking his nose." Physical examination reveals diffuse loss of temperature, pain sensation, proprioception, vibratory perception, and two-point discrimination in the right and left upper and lower distal extremities. A blood culture is ordered, but results are negative. Long term pharmacologic treatment is initiated. One month later, as expected by the physician, the patient presents with decreased serum haptoglobin, and elevated serum lactate dehydrogenase. What is the infectious pathogen?
 
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A 50 year old male who recently travelled to Asia presents to the clinic complaining of "numbness" in his toes and fingers and the sensation that it feels like something is "blocking his nose." Physical examination reveals diffuse loss of temperature, pain sensation, proprioception, vibratory perception, and two-point discrimination in the right and left upper and lower distal extremities. The patient's facial hair is also diffusely diminished . Long term pharmacologic treatment is initiated. One month later, the patient presents with decreased serum haptoglobin, and elevated serum lactate dehydrogenase. What is the infectious pathogen?

Dude.

I was seriously going to do leprosy next.
 
This is so nerdy I gotta jump in. No picture because I'm lazy.

44 year old man has gone to numerous doctors but still has not found a diagnosis. He has numerous complaints. He said it first started months ago with abdominal pain and chronic diarrhea which is consistent with steatorrhea. He also complains of aching pains in the joints of his hands and hips. He has low grade fevers that come and go. Since his symptoms have started, he has lost 33 pounds. He is now noting some hyperpigmentation of his skin. His wife states he has some minor mental status changes and does not "seem himself".

A colonoscopy was performed and was negative for any colon cancer. Workup for inflammatory bowel disease has also been negative. A CT scan showed signs of inflammation of small bowel and enlargement of the related lymph nodes. A biopsy of the small bowel shows thickened villi with copious amounts of macrophages that stain PAS positive.

What is this?
 
This is so nerdy I gotta jump in. No picture because I'm lazy.

44 year old man has gone to numerous doctors but still has not found a diagnosis. He has numerous complaints. He said it first started months ago with abdominal pain and chronic diarrhea which is consistent with steatorrhea. He also complains of aching pains in the joints of his hands and hips. He has low grade fevers that come and go. Since his symptoms have started, he has lost 33 pounds. He is now noting some hyperpigmentation of his skin. His wife states he has some minor mental status changes and does not "seem himself".

A colonoscopy was performed and was negative for any colon cancer. Workup for inflammatory bowel disease has also been negative. A CT scan showed signs of inflammation of small bowel and enlargement of the related lymph nodes. A biopsy of the small bowel shows thickened villi with copious amounts of macrophages that stain PAS positive.

What is this?

Tropheryma whippelii. Classic whipples malabsorption.
 
After traveling to Africa on a medical mission, one of your classmates returns and experiences abdominal pain and constipation, then a progressivly worsening fever. After about 7 days, the fever reaches a plateau and is much more ill, appearing exhausted. The constipation turns into "pea soup" diarrhea! :eek:

During the second week of his disease, he develops a "rose spot" rash which lasts 3-4 days:
rosespotsti7.jpg


What is the diagnosis, are there any concerns this patient should be warned about following treatment?
 
Salmonella typhi.... rose spots gave it away... not sure about the second part however... osteomyelitis maybe, if the PT has sickle cell anemia... but that wouldn't be treatment related...hmm this calls for a review :)

edit...only thing I can think about is.. maybe hyperbilirubinemia or scleral icterus?
 
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Salmonella typhi.... rose spots gave it away... not sure about the second part however... osteomyelitis maybe, if the PT has sickle cell anemia... but that wouldn't be treatment related...hmm this calls for a review :)

edit...only thing I can think about is.. maybe hyperbilirubinemia or scleral icterus?

:thumbup:

second part, does this bug like to camp out anywhere in a way that might affect treatment (or prevent proper tx)?
 
:thumbup:

second part, does this bug like to camp out anywhere in a way that might affect treatment (or prevent proper tx)?

This particular bug enjoys the gallbladder which can be a potential source of recurrent infection. Treatment involves ampicillin or ciprofloxacin and perhaps cholecystectomy.
 
This particular bug enjoys the gallbladder which can be a potential source of recurrent infection. Treatment involves ampicillin or ciprofloxacin and perhaps cholecystectomy.

:thumbup:

(this helped refresh my memory of a very useful image in CMMRS).
 
A 15 year-old male presents to the clinic with a palmar rash characterized by hyperpigmented brown spots. A treatment of topical salicyclic acid is initiated, and the rash resolves in two weeks. What is this?

a10f02.jpg
 
A 15 year-old male presents to the clinic with a palmar rash characterized by hyperpigmented brown spots. A treatment of topical salicyclic acid is initiated, and the rash resolves in two weeks. What is this?

a10f02.jpg

hmm. the pattern of spread and the fact that it responds to Whitfield's ointment... I'm going to go with Tinea Corporis
 
You are close. What is unique about the skin of the palm and soles compared to other areas of the skin? (think relative amount). This pathogen has a predisposition for this layer.

P.S. As a side note, tinea corporis/cruris/etc. represent nomenclature that describe the pathology, which are in turn caused by specific infectious pathogens.
 
You are close. What is unique about the skin of the palm and soles compared to other areas of the skin? (think relative amount). This pathogen has a predisposition for this layer.

P.S. As a side note, tinea corporis/cruris/etc. represent nomenclature that describe the pathology, which are in turn caused by specific infectious pathogens.
It's glaborous skin.

True, but the organism can't generally be distinguished from the rash... to my knowledge.
 
Nota bene: this pathogen has a predisposition for the keratinized layer of skin.

Pathogen is not trichophyton, microsporum, or epidermophyton.
 
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A three year-old boy is brought to the ER by his mother, who is panicked because her son has been nauseous and vomiting recently. You observe that the patient has cutaneous petechiae along his forearms. A blood pressure reading shows that the child has a very depressed pressure, and he soon loses consciousness. Cardioresuscitative support fails and the child is sent for autopsy. At autopsy, the pathologist makes the anatomic diagnosis after examination of this organ <picture1>.

Which organ is displayed?
What is the name of the syndrome?
Which organism is responsible for this boy's demise?
 

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A three year-old boy is brought to the ER by his mother, who is panicked because her son has been nauseous and vomiting recently. You observe that the patient has cutaneous petechiae along his forearms. A blood pressure reading shows that the child has a very depressed pressure, and he soon loses consciousness. Cardioresuscitative support fails and the child is sent for autopsy. At autopsy, the pathologist makes the anatomic diagnosis after examination of this organ <picture1>.

Which organ is displayed?
What is the name of the syndrome?
Which organism is responsible for this boy's demise?

The constellation of symptoms sounds somewhat like H. Influenzae (most likely in this patient) Meningitis causing DIC (and fatal sepsis), but I'm not sure about that path specimen. Looks like something from the CNS.
 
The constellation of symptoms sounds somewhat like H. Influenzae (most likely in this patient) Meningitis causing DIC (and fatal sepsis), but I'm not sure about that path specimen. Looks like something from the CNS.

Meningitis and DIC are right on-however, the organism responsible is most likely to cause the abdominal organ damage shown...Think about other organs that might be affected in the face of fulminant septicemia and which organism might produce this syndrome...
 
A three year-old boy is brought to the ER by his mother, who is panicked because her son has been nauseous and vomiting recently. You observe that the patient has cutaneous petechiae along his forearms. A blood pressure reading shows that the child has a very depressed pressure, and he soon loses consciousness. Cardioresuscitative support fails and the child is sent for autopsy. At autopsy, the pathologist makes the anatomic diagnosis after examination of this organ <picture1>.

Which organ is displayed?
What is the name of the syndrome?
Which organism is responsible for this boy's demise?

Kidney *(superiormost/inferiormost transverse section?) in renal failure-prerenal
Waterhouse-friedrichson
N. Meningitides
 
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Kidney *(superiormost/inferiormost transverse section?) in renal failure-prerenal
Waterhouse-friedrichson
N. Meningitides

:thumbup:

The slice is actually through the adrenal cortex, showing hemorrhage and necrosis throughout. This is characteristic of Waterhouse-Friederichsen syndrome.
 
A 45 year-old American male on tour in Europe presents to an Emergency Department in rural Germany, with complaints of pain in the right side of his chest, and noticeable yellowing of his skin and eyes. He had recently been touring the backwoods of Germany in order to appreciate the foil foliage of the countryside, and ate a variety of the local wild vegetation. Physical examination reveals significant tenderness in the right upper quadrant, scleral icterus, and jaundice. Abdominal CT scan reveals toxin-induced massive hepatic necrosis. The patient was admitted as an inpatient for palliative care due to the extent of his liver failure. Due to the lack of availability of a donor liver, or the presence of a commercially available antitoxin, the PT expired shortly after admission. What organism is this?
 
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