Diagnostic Assessment — Abdomen - Gastroenteritis / Traveller's Diarrhoea
Example 1 of 1 · fictitious patient (Veteran D)
Diagnostic Assessment
Abdomen - Gastroenteritis / Traveller's Diarrhoea
Abdomen - Blastocystis Hominis Infection
No SOP exists under the Veterans' Entitlements Act 1984 for either Gastroenteritis/Traveller's Diarrhoea or Blastocystis Hominis Infection under either the Balance of Probabilities or Reasonable Hypothesis standards.
ADF History
The veteran, Airfield Defence Guard (ADG), enlisted 29 July 1993, currently serving as indicated by active employment status with no termination date specified.
Occupational History
As an Airfield Defence Guard (ADG) in the Royal Australian Air Force, the veteran was exposed to various occupational hazards inherent to the role. This occupation involves providing security and ground defence for RAAF assets, personnel, and installations, both within Australia and on deployment. The role involves physical demands and potential exposure to various environmental conditions. Specific relevant exposures include international deployments which may involve exposure to endemic intestinal pathogens through contaminated food or water, particularly in the Asia-Pacific and an overseas area of operations regions. Post-deployment health screens for an operational deployment noted potential exposure to potentially contaminated water, with the specific comment "Shower water Kabul."
History
The veteran an Airfield Defence Guard in the RAAF, developed traveller's diarrhoea in November 2009 after returning from overseas, which was subsequently diagnosed as a Blastocystis hominis infection. He later experienced another episode of gastroenteritis in June 2013, which was attributed to suspected food poisoning.
Timeline
- 08 Sep 2007. The veteran presented to the base health centre having just returned from overseas with symptoms of vomiting and diarrhoea for one day, which he described as "overseas Belly." The diarrhoea was foul smelling. His partner was also affected with similar symptoms. He reported having been drinking bottled water and eating in good restaurants during his stay in overseas. A faecal specimen was collected and sent for multiplex PCR and M/C/S testing to determine the causative pathogen.
- 10 Sep 2007. Faecal Multiplex PCR results from QML Pathology revealed "Blastocystis species DNA Detected at low level." No other bacterial pathogens or parasites (including Entamoeba histolytica, Giardia, Cryptosporidium, Yersinia, Campylobacter, Shigella, Salmonella, Aeromonas) were detected. The pathology report commented that the role of Blastocystis in causing diarrhoea is controversial, and suggested that a trial of metronidazole may be indicated if symptoms persisted.
- 23 Sep 2007. The veteran attended a follow-up consultation at the base Health Centre. His symptoms of traveller's diarrhoea had improved by this time. He was prescribed Metronidazole 2g stat dose for treatment of the Blastocystis hominis infection that had been detected previously.
- 21 Apr 2011. The veteran presented with symptoms of gastroenteritis that had been present since approximately 18 Apr 2011. He suspected that the cause was consumption of bad food from KFC. He reported experiencing diarrhoea up to ten times daily for 2-3 days, associated with fevers on the first two days that had subsequently resolved. He denied any vomiting or nausea. He had attempted self-treatment with Ciprofloxacin without effect. Clinical examination revealed a systemically well patient with a soft, non-tender abdomen. He was diagnosed with viral gastroenteritis and advised to trial loperamide for symptomatic relief.
Symptoms
During the November 2009 episode, the veteran experienced acute onset of vomiting and diarrhoea, with foul-smelling stool. The symptoms were severe enough to prompt medical consultation, and similar symptoms affected his partner. Stool testing revealed Blastocystis hominis infection at low levels.
During the June 2013 episode, the veteran experienced diarrhoea occurring up to ten times daily for 2-3 days, associated with fevers initially that subsequently resolved. He reported no vomiting or nausea with this episode. The symptoms were severe enough to affect his functionality, prompting medical consultation despite previous unsuccessful self-treatment attempts.
Current symptoms related to these conditions are not documented in the available medical records, suggesting resolution of the acute episodes without chronic sequelae.
Imaging
No imaging studies were performed for these gastrointestinal conditions, as diagnostic imaging is not typically indicated for acute gastroenteritis or parasitic infections unless complications are suspected.
1. What is the formal diagnosis of the condition claimed above?
The formal diagnoses are:
- Gastroenteritis/Traveller's Diarrhoea (ICD-10: A09 - Infectious gastroenteritis and colitis, unspecified)
- Blastocystis Hominis Infection (ICD-10: A07.8 - Other specified protozoal intestinal diseases)
Gastroenteritis is an inflammation of the gastrointestinal tract, specifically the stomach and intestines, typically resulting from viral, bacterial, or parasitic infections. It commonly manifests as diarrhoea, vomiting, abdominal pain, and sometimes fever. Traveller's diarrhoea is a specific form of gastroenteritis that affects individuals traveling to locations where sanitation practices and endemic pathogens differ from those in their home environment. It frequently results from consuming contaminated food or water containing bacterial, viral, or parasitic pathogens to which the traveler has limited immunity.
Blastocystis hominis is a microscopic parasite that can inhabit the digestive tract. While its pathogenicity remains somewhat controversial, it is associated with gastrointestinal symptoms in some individuals, particularly those with compromised immunity or when present in significant numbers. Symptoms may include diarrhoea, abdominal cramping, nausea, and bloating, though asymptomatic carriage is also common.
In the veteran case, these conditions appear to be temporally related as the Blastocystis hominis infection was identified during laboratory investigation of his traveller's diarrhoea episode in November 2009. The subsequent gastroenteritis episode in June 2013 appears to be a separate acute occurrence attributed to suspected food poisoning, with no documented parasitic infection.
2. For each diagnosis identified, please also provide the following dates:
"When did the veteran first experience symptoms attributable to this condition?"
For Gastroenteritis/Traveller's Diarrhoea: The veteran first experienced symptoms on approximately 07 September 2007 (based on presentation date of 5 January with one-day history). A subsequent distinct episode began around 18 Apr 2011.
For Blastocystis Hominis Infection: Symptoms began on approximately 07 September 2007, coinciding with the traveller's diarrhoea episode as the parasite was subsequently identified as a potential causative or contributing factor.
When did the veteran first present to a health / medical provider for this condition?
For Gastroenteritis/Traveller's Diarrhoea: The veteran first presented on 08 September 2007 to the base health centre after returning from overseas. He subsequently presented on 21 Apr 2011 to a healthcare provider (specific name not documented) for the second distinct episode.
For Blastocystis Hominis Infection: The veteran first presented on 08 September 2007 to the base health centre, though the specific diagnosis was not yet established at this initial presentation.
When was the condition confirmed / formally diagnosed?
For Gastroenteritis/Traveller's Diarrhoea: The initial episode was clinically diagnosed on 08 September 2007 at the base health centre. The subsequent episode was diagnosed as viral gastroenteritis on 21 Apr 2011.
For Blastocystis Hominis Infection: The condition was confirmed on 10 September 2007 through faecal Multiplex PCR testing performed by QML Pathology, which detected Blastocystis species DNA at a low level.
When did the veteran first present to you (or your practice) for this condition? 16 November 2017
3. How was this diagnosis confirmed? i.e. what were the key symptoms and signs, investigation results, specialist opinions? Please attach any relevant correspondence and investigation results.
For Gastroenteritis/Traveller's Diarrhoea: The diagnosis was confirmed based on clinical presentation of acute onset diarrhoea and vomiting in November 2009, with a clear temporal relationship to recent travel to overseas. The epidemiological factor of his partner experiencing similar symptoms supported an infectious etiology. In the June 2013 episode, diagnosis was based on clinical presentation of diarrhoea (up to ten times daily) with associated fevers, and suspected association with food consumption.
For Blastocystis Hominis Infection: The diagnosis was confirmed through laboratory investigation. Specifically, a faecal specimen collected on 08 September 2007 was subjected to Multiplex PCR testing at QML Pathology, with results reported on 10 September 2007 confirming the presence of Blastocystis species DNA at a low level. The laboratory report noted that while the role of Blastocystis in causing diarrhoea remains controversial, it may be significant in some cases, particularly when symptoms persist.
4. What do you consider to be the cause(s) of the condition in this veteran? Give consideration to constitutional and common risk factors, pre-existing injuries or diseases, and occupational or lifestyle risks, as well as direct causative mechanisms.
As there are no Statements of Principles (SOPs) for Gastroenteritis/Traveller's Diarrhoea or Blastocystis Hominis Infection, the causative factors must be considered in terms of generally accepted medical principles and scientific evidence.
For Gastroenteritis/Traveller's Diarrhoea:
- Travel to regions with different endemic pathogens and sanitation practices (November 2009 episode)
- MET - the veteran episode of traveller's diarrhoea occurred immediately following return from overseas, a region known to present risk for traveller's diarrhoea due to exposure to novel pathogens and potential differences in food and water safety standards.
- Exposure to contaminated food or water
- MET - While the veteran reported drinking bottled water and eating at good restaurants, exposure to contaminated food or water is the most likely transmission route for travelers acquiring gastrointestinal infections. His partner experiencing similar symptoms strongly suggests a common exposure source.
- Consumption of potentially contaminated or improperly prepared food (June 2013 episode)
- MET - the veteran attributed his gastroenteritis to consumption of "bad KFC," suggesting foodborne illness as the likely cause of this separate episode.
For Blastocystis Hominis Infection:
- Exposure to food or water contaminated with Blastocystis hominis
- MET - Blastocystis hominis is typically acquired through the fecal-oral route, most commonly via consumption of contaminated food or water. The veteran travel to overseas represents a recognized risk factor for acquisition of this parasitic infection.
- International travel to regions with higher prevalence
- MET - Indonesia, including overseas, has a higher prevalence of Blastocystis hominis compared to Australia, making travel to this region a risk factor for infection.
Inability to obtain appropriate clinical management:
- MET - While the veteran did receive medical attention for his conditions, there was a delay between initial presentation (08 September 2007) and specific treatment for Blastocystis (23 September 2007). The Full Federal Court in Brew v Repatriation Commission (14 May 1993) establishes that "inability" encompasses various circumstances that prevent timely and appropriate management. In this case, the delay in specific antiparasitic treatment could constitute an inability to obtain immediate appropriate clinical management, potentially allowing for prolonged symptoms and pathogen carriage.
The % contribution of the causes is 100% and significant
Sequelae
Neither Gastroenteritis/Traveller's Diarrhoea nor the Blastocystis Hominis Infection appear to be sequelae of other conditions documented in the veteran medical history. These represent primary acute gastrointestinal infections rather than secondary complications of other medical conditions.
Unintended Consequence
There is no evidence in the available documentation to suggest that either condition represents an unintended consequence of medical management. Neither condition appears to have developed as a result of treatment administered for another condition.
Inability to Attain Appropriate Medical Management
While the veteran did receive medical care for both conditions, there was a 15-day interval between his initial presentation for gastrointestinal symptoms (08 September 2007) and the administration of specific treatment for Blastocystis hominis (23 September 2007). This delay could potentially represent an inability to attain immediate appropriate medical management for the parasitic infection.
The Full Federal Court in Brew v Repatriation Commission (14 May 1993) established that "inability" encompasses both objective and subjective circumstances that may prevent timely and appropriate management. During military service, various barriers to healthcare access may exist, including operational demands, availability of specialist diagnostic services, and delays in receiving test results.
In this case, the delay in initiating antiparasitic treatment may have allowed for prolonged carriage of the parasite and extended duration of symptoms. While this delay does not appear to have resulted in documented chronic sequelae, it represents a potential factor in the clinical course of his condition.
The % contribution of the causes is 100% and significant
5. Please provide a Health Summary and a medication / prescribing history. -see attached report
