0:00

Right, so let's go to the next case, which is case four.

0:08

So this is a young man in his 30s.

0:13

He was transferred from an outside hospital, and he had down trending leukocytosis.

0:20

He had three weeks of greenish sputum and night sweats with weight loss.

0:25

And this is what his CT looked like when he arrived.

0:29

So we have this area of consolidation and

0:33

a little bit of ground glass opacity around. So looking

0:36

inflammatory to me, and looks inflamed there. And as we come down there

0:41

are other areas, too. So it's multifocal. And they look pretty similar areas

0:45

of consolidation with a little bit of inflammatory looking ground glass

0:51

opacity adjacent. And he's got some systemic symptoms. So let's have our

0:59

next question. Question four. So what is the most likely diagnosis?

1:05

Is this multifocal bacterial pneumonia? Is it metastatic disease? Is it

1:09

TB or is it lymphoma? Yeah, so I think the main concerns here

1:18

are going to be, is this a bacterial pneumonia or

1:21

could this possibly be TB? And I agree lymphoma is not a bad bird in

1:30

the differential. So this is bacterial pneumonia. The way I

1:37

would look at this again, I see this adjacent inflammatory change.

1:44

So I this is going to be in the infective inflammatory spectrum rather

1:49

than lymphoma. Lymphoma can have these areas of consolidation,

1:54

but it's just much less. It's much less common. And when I've seen

1:58

it has been unifocal rather than multifocal like this.

2:06

So for TB, we know that TB can either be miliary, right, which

2:09

is lots of tiny little haematogenous nodules throughout the lungs, or it

2:15

can be endobronchial. And so what to me argues really against TB, despite

2:20

the compelling history of night sweats and weight loss, is that

2:28

really the airways look pretty clean. So we've got this area of consolidation

2:33

with adjacent inflammation, but the airways are not thickened. There's no

2:38

bronchiolitis. There are no other nodules. It's really multifocal areas

2:45

in separate lobes without a lot of airways

2:49

disease. So I would not put TB particularly high. Now, probably some of

2:56

you notice that there is a little bit of air there.

2:58

So that's... Maybe is that a little cavitation? Probably what it is,

3:02

is an abscess actually that is developing on soft tissue windows here. And

3:12

you can see that there is this little bit of air.

3:15

So this means if this is an abscess, this focus of air means

3:20

that the lung is breaking down probably, and there's some

3:24

continuity with one of the airways, one of the larger airways,

3:28

so that we have air just floating, floating within this.

3:32

So this turned out to be an abscess. And one of the things that's

3:36

interesting in looking at lung abscesses as compared to... Excuse me,

3:42

as compared to a cavitating neoplasm, is that the inner surface of an

3:47

abscess tends to be quite smooth. There's a

3:53

wall of reactive tissue around blocking it off.

3:58

And it tends to be very smooth, whereas the outside of a lung

4:02

abscess tends to be rough. So rough on the outside, smooth on the

4:07

inside. That's one of the things I learned when I was doing chest

4:12

in New Zealand. And I don't know that I had really heard that

4:15

much here in the US, but I find that to be quite a

4:17

useful way to think about lung abscess versus neoplasm, so, yeah. So we

4:27

can see that this is low density and it's got thin wall adjacent

4:32

as well. So that's a little lung abscess. Now this had a follow

4:38

up so he went ahead and had his antibiotics and then

4:44

was treated. And this is just a month later.

4:53

And we can see that that area is really much smaller.

4:57

There's a little bit of a pneumatocele remaining, from with this little

5:02

connection to an airway that you can even see there.

5:06

And now in scrolling through this, you see, "Oh, is that a little

5:10

bit of a nodular area?" How worried would you be about that

5:17

for being... Is there still a worry that there's a cancer underlying there?

5:23

I would not be worried personally, because everything is getting so much

5:29

smaller. I don't think I've really seen something get that much smaller

5:35

and then there still be this little cancer that then grew up.

5:38

And maybe somebody's got a case somewhere. But for me

5:42

this is all really behaving as you would expect for infection with abscess

5:49

slowly resolving with a little pneumatocele, and so I like to think about

5:53

these things too in terms of not so much like how afraid am

5:56

I that that's a little cancer that I'm going to miss,

5:59

but more like is this overall picture what I would expect for a

6:03

healing pneumonia? Is there anything really unexpected there? And I don't

6:08

think that there is anything unexpected there. It's following

6:12

a trajectory that is really reasonable a month later.

6:16

And so I would simply recommend another follow up

6:20

and space it further out, in three to six months at this point

6:23

as long as the patient is doing well

6:26

clinically. And so this patient did fine. I do have a companion case

6:32

just to show you what TB does look like, just so we can

6:36

remind ourselves. And you'll see with this that it really does look quite

6:41

different. So this is TB with a cavity. In my experience with TB, when

6:46

you get a cavity, you have a consolidation and then it develops a communication

6:52

with an airway and you get quite a lot of air in it so

6:54

it doesn't go through that liquid abscess phase, and then develop a little

6:59

bit of air, usually goes from these sort of nodular areas to a thick walled

7:04

air cavity. And then as you can see, there's really quite a lot

7:07

of airways disease around in these nodules, there's a lot of bronchiolitis

7:12

and all of the airways in that entire lobe in the apical

7:20

segment of the left upper lobe really look inflamed with quite a lot

7:24

of disease, which goes along with this endobronchial spread.

7:29

So This is a much more typical appearance for TB rather than

7:34

just isolated areas of consolidation and separate lobes. And this is a patient

7:46

of similar age.