Microbiology Nuts & Bolts
  • Home
  • Basic Concepts
    • What is infection?
    • Normal flora
    • Diagnosing infection
  • Microbiology
    • Basic bacterial identification
    • Interpreting bacteriology results
    • Interpreting serology results
  • Infection Control
    • What is infection control?
    • Universal precautions
    • MRSA
    • Clostridium difficile
  • Clinical Scenarios
    • Respiratory infections
    • Urinary infections
    • GI infections >
      • D&V
      • CDAD
    • CNS infections
    • Skin & bone infections
    • Sepsis
  • Antibiotics
    • Antimicrobial Stewardship
    • How antibiotics work
    • How to choose an antibiotic?
    • Reviewing antibiotics
    • Antibiotic resistance
    • Testing antibiotic resistance
    • Penicillin allergy
    • Theraputic Drug Monitoring
  • Guidelines
  • Lectures & Lecture Notes
    • Medical Students
    • Curriculum for the Foundation Program
    • Foundation Year 1
    • Foundation Year 2
    • Other Lectures
  • The Bug Blog
  • Buy the book...
  • NEW Edition Updates
  • Peer Reviews
  • Want to know more?
  • Contact

A Shocking Diagnosis!

7/7/2016

 
A 19 year old woman was admitted with a high fever, low blood pressure and confusion. Her parents reported that she had been complaining about diarrhoea earlier in the day. She was started on IV Cefotaxime for possible meningitis whilst awaiting a lumbar puncture. Fluids were started and she was transferred to the Critical Care department for ongoing supportive treatment. Blood tests showed her to be in renal failure with a low white blood cell count. A lumbar puncture was done and her CSF was completely normal.
 
The patient appeared to be septic but there was no obvious focus of infection. She continued to deteriorate and so she was discussed with the Duty Microbiologist and a provisional diagnosis of toxic shock syndrome was made and IV Clindamycin was added to her treatment. The Critical Care team were advised to check for the presence of any skin or soft tissue focus of infection as well as ensure there was no retained tampon.

​Although no soft tissue focus was found a tampon was present and it was removed. At the time there was noted to be a purulent vaginal discharge and vulvovaginitis.
Picture
Following removal of the tampon and the addition of Clindamycin the patient slowly began to improve. Culture of the pus from the vagina grew a Staphylococcus aureus sensitive to Clindamycin and so the Cefotaxime was stopped. The patient continued to improve.
 
So what is toxic shock syndrome and why is tampon use relevant? 
Toxic shock syndrome (TSS) is a severe infection with a high mortality even when treated appropriately; without treatment it is almost always fatal.
 
TSS is the combination of fever, rash and shock due to toxins produced by certain strains of bacteria, most commonly Group A Beta-haemolytic Streptococcus and Staphylococcus aureus. The mortality from Group A Beta-haemolytic Streptococcus TSS is approximately 30% whereas for Staphylococcus aureus it is normally much less at around 6%.
 
The source of bacteria causing TSS can sometimes be difficult to find and the site of infection may not be apparent; even small amounts of bacteria can produce a lot of toxins. Toxic shock syndrome has classically been associated with the use of tampons, which become colonised with Staphylococcus aureus releasing toxins into the blood, although this has become a lot less common (90% reduction) since the withdrawal of the specific brands of tampons implicated in the original outbreaks back in the early 1980s. Having said this 50% of cases of Staphylococcal TSS are still related to tampon use.
 
Not every Group A Beta-haemolytic Streptococcus or Staphylococcus aureus is capable of causing TSS. In order to cause TSS the bacteria have to produce exotoxins which act as superantigens. These superantigens bypass the normal immune response to antigens and cause lots of T cells to release massive amounts of inflammatory cytokines which then cause capillaries to leak and damage tissues.
 
How does TSS present?
TSS is a clinical diagnosis; there is no specific “laboratory test” for TSS. TSS is confirmed by the presence of the 5 clinical features below; a probable case is suggested by the presence of 4 out of the 5 features. It is still useful to send infected pus or tissue to the laboratory for culture to try and identify the causative bacterium and guide further treatment and public health control measures. In cases of suspected Staphylococcal TSS in women it is also worth sending genital swabs to try and isolate Staphylococcus aureus. Any suspected bacteria can be tested at reference laboratories for the ability to produce exotoxins and cause TSS although this takes time and is not helpful in the initial management of the patient.
 
Clinical Features
  • Fever >39°C
  • Hypotension (often unresponsive to fluids)
  • Erythroderma (resembling sun burn)
  • 3 organ failure from the following:
    • Renal (acute renal failure)
    • Gastrointestinal (diarrhoea)
    • Neurological (encephalopathy)
    • Cardiac (decreased cardiac output)
    • Hepatic (liver failure)
    • Haematogenous (anaemia, thrombocytopaenia)
  • Desquamation 1-2 weeks after illness
 
Many patients with Group A Beta-haemolytic Streptococcal TSS have severe soft tissue infection where pain is more than the physical findings would suggest, and often follows minor trauma at the site. It is thought that the minor trauma occurs in someone who happens to have a brief bacteraemia with the bacterium which settles in the soft tissue due to the localised trauma and then sets up the severe infection.
 
What is the treatment of TSS?
The mainstay of treatment of TSS is supportive care for shock and urgent surgical assessment with a view to surgical resection if the source of infection is apparent, especially when infection follows minor trauma. If a tampon is present in the genital tract this should be removed.
 
Antibiotics are used to target the main causative bacteria, Group A Beta-haemolytic Streptococcus and Staphylococcus aureus. The duration of treatment depends on how quickly the patient responds but rarely needs to be more than 10-14 days.
Toxic Shock Syndrome Treatment
Click for larger image
Both Clindamycin and Linezolid have the benefit of not only damaging the causative bacteria but also inhibiting protein synthesis thereby reducing the amount of toxin the bacterium produces. IV Benzylpenicillin is usually added if Group A Beta-haemolytic Streptococcus is the most likely pathogen and the patient is not allergic to Beta-lactams.
 
Many Microbiologists (including myself) would also consider using IV Immunoglobulin (IVIg) 2g/kg PLUS a further dose 72 hours after if the patient is not improving. The use of IVIg for toxin mediated disease like TSS is an accepted indication as covered in the Clinical Guidelines for Immunoglobulin Use 2nd Edition 2008 produced by the Department of Health UK. IVIg binds the bacterial toxin in the blood stream and helps to prevent it causing damage. In my experience IVIg works very well and often helps stabilise the patient and bring the infection under control much more quickly.
 
Control of TSS in the community
Group A Beta-haemolytic Streptococcus is highly contagious and outbreaks occur in households, schools, nursing homes and other institutions. As a result TSS is a notifiable disease in the UK and there are published guidelines on the investigation and management of contacts of cases of severe Group A Beta-haemolytic Streptococcus infections.
 
There is no specific guideline for Staphylococcal TSS but it is good practice to let the public health team know about cases in case there is a localised outbreak going on. Anyone who either has TSS due to Staphylococcus aureus or who is a household contact found to be a nasal carrier of the same strain of bacteria should be given topical mupirocin ointment to eradicate the carrier state.
 
About 10 days after our patient was admitted the skin on her hands and feet started to peel and the diagnosis of TSS was finally confirmed. Further analysis of the Staphylococcus aureus isolated from the patient confirmed the ability to produce an exotoxin. The patient eventually made a full recovery and went home. Having been decolonised with Mupirocin and Clindamycin there is no particular need for her to avoid future use of tampons although many such patients choose not to “just in case”. If tampons are used they should be of the lowest absorbency and changed regularly, at least 8 hourly or 3 times a day.
Abdelhalim Yousef
11/7/2016 05:41:29 pm

Nice blog.
It seems overlapping with sepsis at least on the beginning of illness


Comments are closed.

    RSS Feed

    Facebook has deleted the Microbiology Nuts & Bolts pages - if you want your weekly dose of microbiology then you will need to come here, and we look forward to you continuing to read it!

    Blog Author:

    David Garner
    Consultant Microbiologist
    Surrey, UK

    Please DO NOT advertise products and conferences on our website or blog

    Categories

    All
    Antibiotic Resistance
    Antibiotics
    Basic Concepts
    Clinical Scenarios
    Guidelines
    Infection Control
    In The News
    Microbiology

    Archives

    November 2022
    October 2022
    September 2022
    August 2022
    July 2022
    June 2022
    May 2022
    April 2022
    March 2022
    February 2022
    January 2022
    December 2021
    November 2021
    October 2021
    September 2021
    August 2021
    July 2021
    June 2021
    May 2021
    April 2021
    March 2021
    February 2021
    January 2021
    December 2020
    November 2020
    October 2020
    September 2020
    August 2020
    July 2020
    June 2020
    May 2020
    April 2020
    March 2020
    February 2020
    January 2020
    December 2019
    November 2019
    October 2019
    September 2019
    August 2019
    July 2019
    June 2019
    May 2019
    April 2019
    March 2019
    February 2019
    January 2019
    December 2018
    November 2018
    October 2018
    September 2018
    August 2018
    July 2018
    June 2018
    May 2018
    April 2018
    March 2018
    February 2018
    January 2018
    December 2017
    November 2017
    October 2017
    September 2017
    August 2017
    July 2017
    June 2017
    May 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    October 2016
    September 2016
    August 2016
    July 2016
    June 2016
    May 2016
    April 2016
    March 2016
    February 2016
    January 2016
    December 2015
    November 2015
    October 2015
    September 2015
    August 2015
    July 2015
    June 2015
    May 2015
    April 2015
    March 2015
    February 2015
    January 2015
    December 2014
    November 2014
    October 2014
    September 2014
    August 2014
    July 2014
    June 2014
    May 2014
    April 2014
    March 2014
    February 2014
    January 2014
    December 2013
    October 2013
    September 2013
    August 2013
    July 2013

    Categories

    All
    Antibiotic Resistance
    Antibiotics
    Basic Concepts
    Clinical Scenarios
    Guidelines
    Infection Control
    In The News
    Microbiology

    RSS Feed

Powered by Create your own unique website with customizable templates.