Thursday, August 13, 2009

Necrotizing Soft Tissue Infection

It started as a small perianal abscess. She didn't seek medical attention, hoping it would just go away. The swelling increased, the pain worsened. She started getting dizzy and nauseous and lightheaded and one night passed out after going for dinner with her family. When I saw her in the ER she was frankly septic and in extremis. Antibiotics and fluids were commenced. I rushed her to the OR.

Fournier's gangrene is a devastating condition. The only hope for cure is rapid, definitive surgical debridement. The CT above suggests the degree of gas gangrene extension in the gluteal and peri-rectal soft tissue spaces. There's nothing fancy about this surgery. You cut and debride until all the necrotic fat and skin and muscle is gone. It leaves a horrible wound. Sometimes you have to divert stool with a colostomy to facillitate clean wound care post-operatively.

Here's the thing. When I was called, I was told I had a patient "to see in the morning" regarding a perianal abscess. I thought, OK. But then I checked the computer at home and saw her WBC count was over 35K. Routine perianal abscesses don't give you white counts that high. So I had them run her through the scanner as I was driving in. The key thing with any necrotizing soft tissue infection (NSTI) is getting the patient to the OR ASAP. And you have to be able to identify those patients who are at high risk for NSTI. Here's some key indicators to assess:

1) Extreme leukocytosis (anything over 20K ought to make you nervous)
2) Hyponatremia (Sodium levels less than 135 strangely enough are almost universally seen with NSTI's. My patient presented with a sodium of 123)
3) Hypotension (well duh, sepsis)
4) Appearance of skin (look for bullae, purplish discoloration, desquamation of skin, etc)
5) Crepitus on exam (anaerobic bacterial production of gas in the subcutaneous tissues)
6) Extreme pain, seemingly out of proportion


Anonymous said...

Yeah sure, Buckeye, you just wanted that outrageous Surgeon's fee, sure you didn't take out her appendix or gall bag too?? Couldn't you have tried one of those Blue Pills for a few days? Hows she gonna get Health Insurance now? Run for Congress??


OHN said...

Buckeye...I will hold franks head under while you flush :)

Ok, so this is one case where having *online medical records doesn't send me over the edge. GREAT CATCH.

*(I have done office transcription for 20 years and am losing clients to EMR--it stinks for me personally, but as a patient, it rocks :)

Anonymous said...

Buckeye, How is she doing, physically as well as mentally?


Bongi said...

pretty impressive scan.

just interested, you leave a perianal abses for the morning? i'd tend to question that.

Jeffrey Parks MD FACS said...

Patient doing very well.

Bongi- Young healthy patient, normal WBC, non-toxic. Yeah, if they call me at midnight, I'll drain it at 6:30AM. Same with appendicitis, mostly. Unless I'm dealing with a kid or a very old patient or a septic patient, no difference in outcome if the appy is done right away or within 12 hours. There's plenty of literature to support such practice.

DHS said...

I agree with the 'impressive scan' comment.

Is the 20k WCC number for all soft tissue infection, or just perianal abscesses? I saw a pretty high WCC with what I thought was simple cellulitis, who I admitted for high dose IVABx, as well as aggressive sugar control. There was no crepitus or rapid spread, just painful red swelling in these huge obese calves that was almost circumferential. I don't think there was much call to be more aggressive.

radinc said...

aha... so this is why the er scans all their perianal abscesses. I always wonder why they need me to measure all those 1.5x2.0cm rim enhancing fluid collections.

I guess they could rely on the excellent clinical features you described in order to triage their patients...

but alas that would require waiting for lab results. faster to send them through the scanner while they prepare the d/c papers.


Guiac said...

Nice Scan. That said anyone who practices medicine and hasn't been fooled by a NSTI that at first glance looks like a run of the mill cellulitis hasn't been doing it long enough. The key is often the rest of the clinical picture- severe sepsis from a simple cellulitis/abscess is rare and should raise the red flag.

Jeffrey Parks MD FACS said...

I actually ordered the scan myself. I've seen a case where a perf sigmoid diverticulitis presented with perineal sepsis. The scan wasn't ordered for diagnostic purposes but rather to plan the inevitable operation. Maybe a waste, but it told me I wouldn't need to do a laparotomy.

Ben said...

Nice catch. Must not have had obvious crepitus or skin changes for them not to order a scan...or was it a case of oversight by the ED?

Dr. Mongo Lloyd said...

I'm still recovering from my necrotizing fasciitis in my right arm. It took three days to diagnose. I didn't get my CT until about an hour before the surgeon decided to operate. This was in November; I still have an open wound. On Feb. 12th, I'm getting the contracture in that arm fixed, and getting Integra applied to prepare for a skin graft. I have pics of the wound online.