Diagnostic Assessment — Acute Infectious Mononucleosis
Example 1 of 1 · fictitious patient (Veteran DP)
Diagnostic Assessment
Acute Infectious Mononucleosis
BOP Code: 18 of 2021 (Acute Infectious Mononucleosis)
RH Code: 17 of 2021 (Acute Infectious Mononucleosis)
ADF History
Veteran DP, date of birth 14 February 1999, Australian Army, Combat Medical Technician (Medic), enlisted 23 January 2017, medically discharged 30 June 2022. Operational service: Iraq, Middle East Area of Operations, 10 January 2019 to 15 July 2019 (warlike).
Occupational History
Combat medical technicians provide first aid, resuscitation and primary health care to soldiers in barracks, on exercise and on operations. The trade involves close physical contact with casualties, including airway management and rescue breathing, handling of blood and body fluids, and treating respiratory and gastrointestinal infections in crowded accommodation. Medics also carry the same loads and complete the same field training as the soldiers they support.
On deployment, personnel live and work in close quarters, share vehicles, eating utensils and water containers, and are exposed to outbreaks of respiratory and viral illness that spread readily through a contingent. Diagnostic pathology is limited in theatre, and personnel are expected to keep working through minor illness.
History
Veteran DP, a combat medic in the Australian Army, developed acute infectious mononucleosis on 28 June 2019 on warlike service in Iraq, after sharing a hydration system with a section member who was confirmed to have Epstein-Barr virus infection and after giving unprotected rescue breaths to a casualty in early June 2019. The illness was severe, with tonsillar airway narrowing, hepatitis, marked splenomegaly and a splenic subcapsular haematoma, and was followed by a prolonged post-infectious fatigue syndrome.
Timeline
- 02 Dec 2018 — Pre-deployment medical examination at the garrison health centre. The veteran was well, passed her basic fitness assessment and had a normal examination with no lymphadenopathy, a normal throat and no palpable spleen. Full blood count and liver function tests were normal. She was assessed as fit for warlike service in Iraq. "fit to deploy, FBC/LFT normal"
- 04 Jun 2019 — Entry in the section health log during a three-day training serial with Iraqi army trainees at the range complex. The temperature reached 47 degrees and resupply of water bottles failed. The veteran shared the mouthpiece of a section member's hydration bladder throughout the serial. That soldier was seen six days later with fever, sore throat and lymphadenopathy, and EBV serology confirmed acute infectious mononucleosis. "shared hydration bladder, index case"
- 06 Jun 2019 — Incident report and medic treatment record. At the range complex an Iraqi trainee collapsed in respiratory arrest after a heat injury. The pocket mask from the veteran's medical pack had been damaged and replacement stock had not arrived, so she gave mouth-to-mouth rescue breaths for about six minutes until a bag-valve mask was brought forward. Saliva and vomitus entered her mouth. The trainee was evacuated and survived. "unprotected rescue breaths, saliva exposure"
- 01 Jul 2019 — Seen by the medical officer at the role 2 facility. Four days of fever to 39.4 degrees, severe sore throat, fatigue and myalgia since 28 June 2019. Examination showed exudative tonsillitis with kissing tonsils, tender cervical lymphadenopathy and a palpable spleen 4 centimetres below the costal margin. Blood film showed 28 per cent atypical lymphocytes and the heterophile antibody test was positive. EBV-specific serology was not available in theatre. "kissing tonsils, Monospot positive"
- 03 Jul 2019 — Admitted to the role 3 hospital with stridor and difficulty swallowing. She received intravenous dexamethasone and fluids. ALT was 412 U/L and bilirubin 38 micromol/L. Ultrasound showed splenomegaly of 16.5 centimetres. She was aeromedically evacuated to Australia on 06 July 2019, where CT showed a small splenic subcapsular haematoma. "stridor, hepatitis, spleen 16.5 cm"
- 08 Jul 2019 — Infectious diseases consultation at a tertiary hospital in Australia. EBV viral capsid antigen IgM was positive and IgG weakly positive, with EBV nuclear antigen IgG negative, confirming recently acquired Epstein-Barr virus infection. The physician confirmed acute infectious mononucleosis complicated by hepatitis, upper airway narrowing and splenic haematoma, and advised no exertion or contact activity for at least eight weeks. "VCA IgM positive, EBNA negative"
- 20 Sep 2019 — Follow-up ultrasound showed the spleen reduced to 12.8 centimetres with resolution of the haematoma, and liver function had normalised. She remained profoundly fatigued, could not walk more than one kilometre and had poor concentration and unrefreshing sleep. A graduated return to work was commenced. "spleen 12.8 cm, ongoing fatigue"
- 14 Jun 2021 — Infectious diseases and general medical review. Two years after the illness she still had post-exertional fatigue, unrefreshing sleep and cognitive slowing, and could not complete her basic fitness assessment. A post-infectious fatigue syndrome following Epstein-Barr virus infection was diagnosed. She was referred for medical employment classification review, leading to discharge in June 2022. "post-infectious fatigue syndrome"
Symptoms
At onset the veteran had high fever, severe sore throat with painful swallowing, profound fatigue, aching muscles and tender swollen glands in the neck. Within days she developed noisy breathing and difficulty swallowing from tonsillar enlargement, left upper abdominal discomfort from splenic enlargement and mild jaundice.
The acute illness lasted about six weeks. Since then she has had persisting fatigue that worsens for one to two days after physical or mental effort, unrefreshing sleep, poor concentration and memory, recurrent sore throats and tender neck glands when run down. She works part time and no longer runs or plays sport.
Imaging
- 03 Jul 2019 — Ultrasound abdomen: "Splenomegaly, 16.5 centimetres in length, with homogeneous echotexture. Mild hepatomegaly. No free fluid."
- 06 Jul 2019 — CT abdomen with contrast: "Splenomegaly with a small subcapsular haematoma along the lateral border of the spleen, measuring 2.1 by 0.8 centimetres. No active bleeding and no free fluid."
- 20 Sep 2019 — Ultrasound abdomen: "Spleen reduced to 12.8 centimetres. Resolution of the subcapsular haematoma. Normal liver."
Onset Date
The most likely date of onset of this condition is 28 Jun 2019.
At that date the veteran was on warlike service in Iraq as the medic attached to a training team instructing Iraqi army soldiers. On 28 June 2019 she developed fever, sore throat and marked fatigue, followed within days by tonsillar enlargement, lymphadenopathy and splenomegaly.
This date is appropriate because her pre-deployment medical examination of 02 December 2018 was normal, with no lymphadenopathy or splenomegaly and a normal blood count, and she was well and working full duties until late June 2019. She first presented on 01 July 2019, reporting four days of illness, and recently acquired Epstein-Barr virus infection was confirmed on serology on 08 July 2019.
For the exposure factors, the period between 12 and 50 days before onset runs from 09 May 2019 to 16 Jun 2019. Within that window she shared the hydration bladder mouthpiece of a section member with confirmed infectious mononucleosis from 04 Jun 2019 to 06 Jun 2019, 22 to 24 days before onset, and gave unprotected mouth-to-mouth rescue breaths to a casualty on 06 Jun 2019, 22 days before onset. Both exposures occurred in the course of her duties on warlike service and fall within the usual incubation period of four to six weeks.
For the clinical management factor, the period of concern runs from onset on 28 Jun 2019 to evacuation on 06 Jul 2019, during which EBV-specific serology, liver function monitoring and imaging were unavailable or delayed in theatre and she continued duties for three days with an enlarged spleen.
1. What is the formal diagnosis of the condition claimed above?
The formal diagnosis is Acute Infectious Mononucleosis (ICD-10 B27.0), caused by Epstein-Barr virus and complicated by hepatitis, upper airway narrowing and a splenic subcapsular haematoma, under the Statements of Principles concerning acute infectious mononucleosis, Balance of Probabilities No. 18 of 2021 and Reasonable Hypothesis No. 17 of 2021.
Acute infectious mononucleosis is the illness caused by primary infection with the Epstein-Barr virus, a herpesvirus spread mainly through saliva and less commonly through blood products and transplanted tissue. After an incubation period of about four to six weeks it causes fever, pharyngitis, cervical lymphadenopathy, splenomegaly and marked fatigue, with atypical lymphocytes on the blood film. Complications include airway obstruction from tonsillar enlargement, hepatitis, splenic rupture and a prolonged post-infectious fatigue state. It is most common in young adults living in close quarters, such as military recruits and deployed personnel.
The illness began on 28 June 2019 on warlike service in Iraq, was confirmed by serology on 08 July 2019 and was followed by a persisting post-infectious fatigue syndrome.
2. For each diagnosis identified, please also provide the following dates:
When did the veteran first experience symptoms attributable to this condition?
28 June 2019.
When did the veteran first present to a health / medical provider for this condition?
01 July 2019.
When was the condition confirmed / formally diagnosed?
08 July 2019.
When did the veteran first present to you (or your practice) for this condition?
21 May 2025.
3. How was this diagnosis confirmed? i.e. what were the key symptoms and signs, investigation results, specialist opinions?
The diagnosis was confirmed on 08 July 2019 by Epstein-Barr virus serology showing a positive viral capsid antigen IgM, a weakly positive viral capsid antigen IgG and a negative EBV nuclear antigen IgG, which is the pattern of recently acquired infection. This is laboratory evidence of recently acquired Epstein-Barr virus infection accompanying an illness caused by it, which meets the Statement of Principles definition.
The clinical features were typical: fever, exudative pharyngitis with kissing tonsils, tender cervical lymphadenopathy, splenomegaly of 16.5 centimetres on ultrasound, hepatitis with an ALT of 412 U/L, 28 per cent atypical lymphocytes on the blood film and a positive heterophile antibody test on 01 July 2019. An infectious diseases physician confirmed the diagnosis, and the course, including the CT-confirmed splenic subcapsular haematoma and gradual recovery of spleen size and liver function by September 2019, was consistent.
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.
Legislation: the clinical onset of this condition was on 28 June 2019, after 1 July 2004, during continuous full-time service. This is a Military Rehabilitation and Compensation Act 2004 (MRCA) claim and the Statements of Principles apply. The Reasonable Hypothesis instrument applies to the veteran's warlike service in Iraq in 2019, where the exposures and the onset occurred. The Balance of Probabilities instrument applies to peacetime service; its factors are identical in this instrument and are also set out and met on the same facts.
Each factor must be related to the person's relevant service. Under the beneficial approach required by the legislation, the absence of documentation does not mean that an event or exposure did not occur: lack of evidence is not evidence of lack. Exposure to the Epstein-Barr virus is rarely documented at the time; here it was recorded because the source case was confirmed and the rescue breathing was the subject of an incident report.
Balance of Probabilities — Statement of Principles concerning Acute Infectious Mononucleosis, No. 18 of 2021
Causative factors
Factor 9(1): being exposed to the Epstein-Barr virus between 12 and 50 days before the clinical onset of acute infectious mononucleosis; — MET
- From 04 June 2019 to 06 June 2019, 22 to 24 days before onset on 28 June 2019, the veteran shared the hydration bladder mouthpiece of a section member during a range serial when water resupply failed. That soldier was diagnosed with acute infectious mononucleosis on 10 June 2019, confirmed by EBV serology, and was shedding the virus in saliva at the time. On 06 June 2019 she also gave mouth-to-mouth rescue breaths without a barrier device for about six minutes, with saliva entering her mouth. Each is exposure of the oral mucosa to saliva infected with the Epstein-Barr virus, as defined, within the 12 to 50 day window from 09 May 2019 to 16 June 2019, and each arose from her duties.
Worsening factors
Factor 9(2): inability to obtain appropriate clinical management for acute infectious mononucleosis. — MET
- EBV-specific serology, serial liver function testing and abdominal imaging were not available at the role 2 facility, and the veteran continued medic duties, including lifting stretchers and wearing body armour, for three days after the illness began with an enlarged spleen. She was not imaged until 03 July 2019, after stridor developed, and a splenic subcapsular haematoma was found on 06 July 2019. Under Brew v Repatriation Commission (1999) this is an inability to obtain appropriate clinical management, and it contributed to the splenic haematoma and the severity of the illness.
Reasonable Hypothesis — Statement of Principles concerning Acute Infectious Mononucleosis, No. 17 of 2021
Causative factors
Factor 9(1): being exposed to the Epstein-Barr virus between 12 and 50 days before the clinical onset of acute infectious mononucleosis; — MET
- On warlike service in Iraq, the veteran shared the hydration bladder of a section member with serologically confirmed infectious mononucleosis from 04 June 2019 to 06 June 2019, and gave unprotected rescue breaths to a collapsed Iraqi trainee on 06 June 2019 because replacement pocket masks had not been delivered. These exposures of her oral mucosa to infected saliva occurred 22 to 24 days before onset on 28 June 2019, within the window from 09 May 2019 to 16 June 2019, and arose directly from the conditions and duties of her warlike service.
Worsening factors
Factor 9(2): inability to obtain appropriate clinical management for acute infectious mononucleosis. — MET
- On warlike service in Iraq, specific serology, liver monitoring and imaging were unavailable at the role 2 facility, the veteran continued strenuous duties with splenomegaly, and she required evacuation to Australia after developing stridor, hepatitis and a splenic subcapsular haematoma.
The % contribution of the causes is 100% and significant.
Sequelae
The veteran has developed a post-infectious fatigue syndrome following Epstein-Barr virus infection, diagnosed by an infectious diseases physician on 14 June 2021, with post-exertional fatigue, unrefreshing sleep and cognitive slowing persisting for more than two years. This is a recognised sequela of acute infectious mononucleosis, particularly after severe illness. The loss of her career and fitness has been associated with low mood, recorded by her general practitioner in 2021. The splenic subcapsular haematoma was a direct complication of the acute illness and resolved without surgery.
Unintended Consequence
Met. Insomnia, agitation and a rise in blood glucose to 11.2 mmol/L were recorded during the course of high-dose intravenous dexamethasone given for tonsillar airway narrowing at the role 3 hospital on 03 July 2019. These are unintended consequences of treatment provided and paid for by the Commonwealth while the veteran was serving (section 6A of the DRCA and the equivalent provisions of the MRCA).
Inability to Attain Appropriate Medical Management
MET. On warlike service in Iraq the veteran could not obtain the investigations needed to diagnose and monitor infectious mononucleosis promptly: EBV-specific serology, serial liver function tests and abdominal imaging were not available at the role 2 facility. Without a confirmed diagnosis and with an enlarged spleen, she continued medic duties, including stretcher carries in body armour, for three days, and was imaged only after she developed stridor. A splenic subcapsular haematoma was found on 06 July 2019. Applying the objective and subjective tests in Brew v Repatriation Commission (Full Federal Court, 10 September 1999, Merkel J), the unavailability of appropriate investigation and activity restriction in an operational setting amounts to an inability to obtain appropriate clinical management, and it materially contributed to the severity of her illness.
5. Please provide a Health Summary and a medication / prescribing history.
See attached report.
References
- 02 Dec 2018, Pre-deployment medical examination and pathology, Medical Officer, Garrison health centre
- 04 Jun 2019, Section health log, Medic, Iraq
- 06 Jun 2019, Incident report and treatment record, Training team, Iraq
- 10 Jun 2019, Outpatient health record and EBV serology of the source case, Medical Officer, Iraq
- 01 Jul 2019, Outpatient health record, blood film and heterophile antibody test, Medical Officer, Role 2 facility, Iraq
- 03 Jul 2019, Admission record and ultrasound abdomen, Role 3 hospital
- 06 Jul 2019, CT abdomen, Radiologist
- 08 Jul 2019, Infectious diseases consultation and EBV serology, Infectious diseases physician
- 20 Sep 2019, Ultrasound abdomen and liver function tests, Radiologist and General practitioner
- 14 Jun 2021, Specialist review, Infectious diseases physician
- Statement of Principles concerning Acute Infectious Mononucleosis (Balance of Probabilities) No. 18 of 2021, Repatriation Medical Authority
- Statement of Principles concerning Acute Infectious Mononucleosis (Reasonable Hypothesis) No. 17 of 2021, Repatriation Medical Authority
