0:00

The next couple cases are different pathogens.

0:04

First I'll show you a patient who had histoplasmosis.

0:08

This patient started out with a chest radiograph

0:11

and we can see that there is obviously a large area

0:14

of consolidation in the left upper part of the chest.

0:18

Just looking at the patient's bones, we can tell

0:20

that they are too old to have a large thymus like we would

0:23

expect in a newborn.

0:25

So we see this large area of consolidation.

0:28

When we look at the lateral, we can see that

0:31

a budding the major fisure as well.

0:35

So this patient went on to have a CT scan.

0:38

They have a contrast enhanced CT scan will start

0:41

with the axial soft tissue windows

0:43

and right in the middle of the chest we can see a large soft

0:46

tissue structure that's heterogeneously enhancing

0:50

centrally more hypo dense and peripherally enhancing.

0:54

If we keep our eye on that

0:55

and follow it, we see other areas

0:58

that are similar elsewhere in the mediastinum

1:01

and these are all necrotic areas of lymph adenopathy.

1:08

Additionally, we can see consolidation

1:11

in the left upper lobe and if we switch to our lung windows

1:16

and get a better appreciation

1:17

for the lung parenchymal involvement,

1:20

you can see ground glass opacities elsewhere in

1:23

that left lung as well

1:25

as additional consolidation associated with lymphadenopathy

1:30

in the left hilar region.

1:33

So something that's important to note as we go through the

1:38

ronal and sagittal images as well is

1:41

that I had mentioned earlier with

1:44

mycobacterium tuberculosis infections

1:47

that you can often see lymphadenopathy

1:49

with central necrosis.

1:52

This is also the case

1:53

with histoplasmosis In the acute phase.

1:55

You can see lymphadenopathy with central necrosis

1:58

and depending on where you are,

2:00

if histoplasmosis is endemic,

2:02

this might be the more likely diagnosis rather

2:04

than tuberculosis.

2:07

On this sagittal sequence, we can nicely see the demarcation

2:10

of the consolidation on that left side.

2:16

And another thing to note on the soft tissue images is

2:20

that we include the upper abdomen in our scan

2:24

and we can see in the spleen there are several

2:27

small focal hypodense regions.

2:31

I don't think we get all the way through the spleen,

2:32

but we do see a few

2:33

of those scattered throughout the spleen.

2:35

And that can also be seen with histoplasmosis.

2:39

In the chronic phase of histoplasmosis,

2:43

we often see calcified granuloma.

2:45

Those may be in the spleen, they may be in the liver,

2:48

they may be in the lungs,

2:50

and they may be in the mediastinum.

2:52

So all these big necrotic lymph nodes can eventually calcify

2:55

and that's what we might see later on when it becomes

2:58

chronic.