Viral Meningitis — DVA claim example

Diagnostic Assessment — Viral Meningitis

Example 1 of 1 · fictitious patient (Veteran AL)

Diagnostic Assessment

Viral Meningitis

No Statement of Principles applies to this condition (non-SOP claim).

ADF History

Veteran AL, date of birth 03 November 1985, Australian Army, Rifleman (Infantry), enlisted 14 January 2004, medically discharged 27 February 2014. Operational service: Solomon Islands, 05 July 2005 to 10 November 2005 (non-warlike); Afghanistan, 12 February 2010 to 20 October 2010 (warlike).

Occupational History

As an infantry rifleman the veteran conducted dismounted foot patrols carrying 35 to 45 kilograms, lived for long periods in austere patrol bases and field locations with shared sleeping quarters, limited water, poor sanitation and rodent and insect infestation, and waded rivers and irrigation canals.

Infantry soldiers are routinely exposed to communicable diseases in crowded accommodation, to arthropod-borne infections in endemic regions, and to blood and body fluids when providing first aid to casualties. Access to definitive medical care from forward locations depends on aeromedical evacuation.

History

Veteran AL, an infantry rifleman in the Australian Army, developed viral meningitis on 18 August 2010 at a remote patrol base during warlike service in Afghanistan, with enterovirus and herpes simplex virus type 2 detected in his cerebrospinal fluid, against a background of primary HIV infection from a needle-stick injury, prednisolone treatment and undiagnosed common variable immunodeficiency. The meningitis recurred more severely in June 2012 when his immunoglobulin replacement lapsed.

Timeline

• 20 Jan 2010 — At his pre-deployment health assessment the veteran was well, with no history of meningitis or neurological illness. Serum protein testing showed an IgG of 3.4 g/L, flagged as below the reference range, but no follow-up was arranged before he deployed to Afghanistan on 12 February 2010. "IgG 3.4, fit to deploy"
• 02 Jul 2010 — While providing first aid to a wounded local national after an improvised explosive device strike near the patrol base, the veteran sustained a needle-stick injury from a used cannula. Post-exposure prophylaxis was not available until 07 July 2010. On 10 July 2010 the medical officer started prednisolone 25 mg daily for severe atopic dermatitis. "needle-stick injury, PEP delayed"
• 29 Jul 2010 — After mid-tour leave the veteran presented with a first episode of genital ulceration, and herpes simplex virus type 2 was confirmed on PCR with negative type-specific serology. From 25 July he was living in a room shared with 27 other soldiers, with heavy rodent and sandfly infestation. An interpreter living with the section developed mumps on 01 August. "primary genital HSV-2"
• 09 Aug 2010 — The medical officer diagnosed right T6 herpes zoster. Three soldiers in the veteran's room had developed a febrile diarrhoeal illness from 04 August, with enterovirus confirmed on stool PCR on 09 August. The veteran had waded through sewage-contaminated irrigation canals on repeated patrols and fell into one on 11 August. "right T6 zoster, enterovirus cluster"
• 18 Aug 2010 — On patrol the veteran developed a sudden severe headache, fever of 39.4 degrees, neck stiffness, photophobia and vomiting. The medic recorded meningism with a normal conscious state. Aeromedical evacuation was delayed by enemy activity and dust storms and he reached the role 3 hospital on 20 August. "headache, neck stiffness, photophobia"
• 20 Aug 2010 — At the role 3 hospital a lumbar puncture showed 420 white cells per microlitre, 85 per cent lymphocytes, protein 1.1 g/L and glucose 3.2 mmol/L with a serum glucose of 5.6 mmol/L. Gram stain and culture were negative. CSF PCR was positive for enterovirus and herpes simplex virus type 2. Mumps IgM was positive. A physician diagnosed viral meningitis and started intravenous aciclovir. "lymphocytic CSF, enterovirus PCR positive"
• 12 Nov 2010 — After his return to Australia, HIV infection was confirmed, with RNA detected on 30 August and seroconversion on 30 September 2010. A clinical immunologist diagnosed common variable immunodeficiency, with an IgG of 3.1 g/L and absent vaccine responses, and started monthly intravenous immunoglobulin. He had persisting headaches and poor concentration. "CVID, IVIG commenced, HIV confirmed"
• 14 Jun 2012 — After three months without immunoglobulin replacement and six weeks off antiretroviral therapy, the veteran presented to hospital from his base in Australia with severe headache, fever, neck stiffness and confusion. CSF showed 980 white cells per microlitre and herpes simplex virus type 2 on PCR. MRI showed leptomeningeal enhancement. He required eight days of intravenous aciclovir and was left with daily headache and impaired concentration. "recurrent meningitis, CSF 980 cells"

Symptoms

At onset the veteran had a sudden severe headache, fever, neck stiffness, photophobia, nausea and vomiting, with malaise and myalgia. The acute symptoms settled over about three weeks, but he was left with recurrent headaches, fatigue and poor concentration. The recurrence in June 2012 was more severe, with confusion, and was followed by daily headaches.

He now reports daily headaches, worse with exertion and bright light, fatigue, poor short-term memory and concentration, word-finding difficulty when tired, and anxiety about further episodes. Neuropsychological testing in 2013 showed reduced processing speed and working memory. He no longer works full time and avoids driving long distances.

Imaging

• 20 Aug 2010 — CT brain (non-contrast), role 3 hospital: "No intracranial haemorrhage, mass or hydrocephalus. Performed before lumbar puncture."
• 15 Jun 2012 — MRI brain with gadolinium: "Diffuse smooth leptomeningeal enhancement over both cerebral convexities without parenchymal signal change, consistent with meningitis. No abscess or hydrocephalus."

Onset Date

The most likely date of onset of this condition is 18 Aug 2010.

At that date the veteran was on warlike service in Afghanistan, at a remote patrol base in Uruzgan Province, conducting daily foot patrols. He developed sudden headache, fever, neck stiffness and photophobia while on patrol.

This date is appropriate because the regimental aid post recorded him as well, apart from his zoster rash and dermatitis, at review on 16 August 2010, and the medic recorded meningism on 18 August 2010. Cerebrospinal fluid taken on 20 August 2010 confirmed viral meningitis. The date falls within his warlike deployment.

For the contact factors, the 14 days before onset run from 04 Aug 2010 to 18 Aug 2010, during which he shared a room with soldiers with confirmed enteroviral illness, waded through contaminated canals and developed zoster on 09 Aug 2010. The 21 days before onset run from 28 Jul 2010 to 18 Aug 2010, during which he was bitten nightly by sandflies and handled rodent nesting material. The 25 days before onset run from 24 Jul 2010 to 18 Aug 2010, covering his contact with the interpreter with mumps, and the 30 days before onset run from 19 Jul 2010 to 18 Aug 2010, during which he slept in crowded accommodation from 25 Jul 2010. The 4 weeks before onset run from 21 Jul 2010 to 18 Aug 2010, covering his primary genital herpes on 29 Jul 2010, and the 8 weeks before onset run from 23 Jun 2010 to 18 Aug 2010, covering the needle-stick injury of 02 Jul 2010. He took prednisolone 25 mg daily from 10 Jul 2010 to 20 Aug 2010, and his immunodeficiency was documented before deployment. He also developed right T6 herpes zoster on 09 Aug 2010, a marker of the immunosuppression present in the days before onset.

For the worsening factors, the documented worsening is the more severe recurrence on 14 Jun 2012. The 14 days before it run from 31 May 2012 to 14 Jun 2012, covering the genital herpes recurrence of 06 Jun 2012. HIV infection and common variable immunodeficiency were present on that date, and his immunoglobulin replacement had lapsed from March 2012.

1. What is the formal diagnosis of the condition claimed above?

The formal diagnosis is Viral Meningitis (ICD-10-AM A87.9), with enterovirus and herpes simplex virus type 2 detected in the cerebrospinal fluid, followed by a recurrence in 2012. No Statement of Principles has been determined for viral meningitis.

Viral meningitis, also called aseptic meningitis, is inflammation of the membranes covering the brain and spinal cord caused by a viral infection. Enteroviruses are the most common cause, followed by herpes simplex virus type 2, varicella-zoster virus, HIV, mumps, arthropod-borne viruses and lymphocytic choriomeningitis virus. It presents with headache, fever, neck stiffness and photophobia, with a lymphocytic cerebrospinal fluid, normal glucose and negative bacterial cultures. Most cases resolve, but immunocompromised people can have severe, prolonged or recurrent illness, and persisting headache, fatigue and cognitive symptoms are common.

The condition began on 18 August 2010 during warlike service in Afghanistan, was confirmed on lumbar puncture on 20 August 2010 and recurred more severely on 14 June 2012.

2. For each diagnosis identified, please also provide the following dates:

When did the veteran first experience symptoms attributable to this condition?

18 August 2010.

When did the veteran first present to a health / medical provider for this condition?

18 August 2010.

When was the condition confirmed / formally diagnosed?

20 August 2010.

When did the veteran first present to you (or your practice) for this condition?

09 April 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 lumbar puncture on 20 August 2010, which showed a lymphocytic pleocytosis of 420 white cells per microlitre, a mildly raised protein, a normal CSF to serum glucose ratio, a negative Gram stain and culture, and positive PCR for enterovirus and herpes simplex virus type 2. This, with the clinical picture of fever, headache, neck stiffness and photophobia and a normal conscious state, establishes viral meningitis and excludes bacterial meningitis and encephalitis.

The recurrence on 14 June 2012 was confirmed by a cerebrospinal fluid pleocytosis of 980 white cells per microlitre with herpes simplex virus type 2 on PCR and leptomeningeal enhancement on MRI.

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.

No Statement of Principles has been determined by the Repatriation Medical Authority for viral meningitis. The claim is therefore decided on the sound medical-scientific evidence of what causes the condition, without the limits a Statement of Principles would impose. The recognised causes below are drawn from that evidence and phrased in the same way as Statement of Principles factors.

Legislation: the clinical onset of this condition was on 18 August 2010, after 1 July 2004, during warlike service in Afghanistan. This is a Military Rehabilitation and Compensation Act 2004 (MRCA) claim. Because the onset occurred on warlike service, the reasonable hypothesis standard of proof applies; the balance of probabilities standard applies to peacetime service, which covers the recurrence in Australia in 2012. Each cause must be related to the person's 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.

Recognised causes on the medical-scientific evidence (no Statement of Principles)

Causative factors

Cause 1: being in close contact with a person who has an enteroviral infection within the 14 days before the clinical onset of viral meningitis; — MET

- On 04 August 2010, at a patrol base in Uruzgan Province, Afghanistan, three soldiers sharing the veteran's room developed fever, headache and diarrhoea, and enterovirus was confirmed by PCR on stool in two of them on 09 August 2010. The veteran shared sleeping space, a water point and ration preparation with them from 04 to 12 August 2010, 6 to 14 days before his onset on 18 August 2010. Enterovirus was detected in his own cerebrospinal fluid on 20 August 2010.

Cause 2: living or sleeping in crowded accommodation for at least 7 days within the 30 days before the clinical onset of viral meningitis; — MET

- From 25 July 2010 the veteran lived in a single mud-brick room shared by 28 soldiers at the patrol base, with stretchers less than one metre apart and no running water. He slept there every night from 25 July to 18 August 2010, 24 days within the 30 days before onset, from 19 July 2010 to 18 August 2010.

Cause 3: swimming in, wading through or ingesting water contaminated with human faeces or sewage within the 14 days before the clinical onset of viral meningitis; — MET

- Patrol reports record that the veteran waded chest-deep through irrigation canals that carried village sewage on at least six patrols between 05 and 15 August 2010, within the 14 days before onset from 04 August 2010 to 18 August 2010, and on 11 August 2010 he fell fully into a canal and swallowed water. Enteroviruses are spread by the faecal-oral route.

Cause 4: being bitten by sandflies or mosquitoes in a region where an arthropod-borne virus that causes meningitis is endemic within the 21 days before the clinical onset of viral meningitis; — MET

- Sandfly fever and Toscana-type phleboviruses, which cause aseptic meningitis, are endemic in southern Afghanistan. The veteran recorded dozens of sandfly bites a night on the patrol base between 28 July and 18 August 2010, within the 21 days before onset from 28 July 2010 to 18 August 2010, and the medical officer treated him for infected bites on 06 August 2010. Permethrin-treated bed nets were not available at the base.

Cause 5: being exposed to the excreta or nesting material of rodents within the 21 days before the clinical onset of viral meningitis; — MET

- The patrol base compound was infested with house mice and rats. The veteran's section cleared nesting material from the room and storeroom by hand on 30 July and 08 August 2010, and droppings were found on stretchers and ration packs throughout August 2010, within the 21 days before onset. Lymphocytic choriomeningitis virus, carried by house mice, causes viral meningitis.

Cause 6: having a primary genital infection with herpes simplex virus type 2 within the 4 weeks before the clinical onset of viral meningitis; — MET

- The veteran presented to the regimental aid post on 29 July 2010, after mid-tour leave, with a first episode of painful genital ulceration. Herpes simplex virus type 2 was confirmed by PCR on a swab with negative type-specific serology, establishing primary infection, 20 days before onset and within the 4 weeks from 21 July 2010 to 18 August 2010. Herpes simplex virus type 2 was also detected in his cerebrospinal fluid on 20 August 2010.

Cause 7: having primary infection with human immunodeficiency virus within the 8 weeks before the clinical onset of viral meningitis; — MET

- On 02 July 2010 the veteran sustained a needle-stick injury from a cannula used on a wounded local national while providing first aid after an improvised explosive device strike. Post-exposure prophylaxis was not available at the patrol base for five days. HIV RNA was detected on 30 August 2010 with negative antibody testing, and seroconversion followed on 30 September 2010, confirming primary infection acquired 6 weeks and 5 days before onset, within the 8 weeks from 23 June 2010 to 18 August 2010. Aseptic meningitis is a recognised feature of acute HIV infection.

Cause 8: being in close contact with a person who has mumps within the 25 days before the clinical onset of viral meningitis; — MET

- An Afghan interpreter who lived and ate with the veteran's section developed bilateral parotitis on 01 August 2010 and mumps was confirmed on serology. The veteran was in daily close contact with him from 25 July to 03 August 2010, within the 25 days before onset from 24 July 2010 to 18 August 2010. His own mumps IgM was positive on 20 August 2010.

Cause 9: taking a drug which suppresses the immune system, including prednisolone at a dose of at least 20 milligrams per day, for at least 2 weeks before the clinical onset of viral meningitis; — MET

- The medical officer prescribed prednisolone 25 mg daily on 10 July 2010 for a severe flare of atopic dermatitis aggravated by heat, sweat and dust at the patrol base, and the veteran took it continuously until 20 August 2010. He had therefore taken 25 mg a day for 5 weeks and 4 days before onset on 18 August 2010.

Cause 10: having hypogammaglobulinaemia or common variable immunodeficiency at the time of the clinical onset of viral meningitis; — MET

- Pre-deployment serum protein testing on 20 January 2010 showed an IgG of 3.4 g/L, flagged as low but not followed up before deployment. A clinical immunologist diagnosed common variable immunodeficiency on 12 November 2010, with an IgG of 3.1 g/L, low IgA and IgM and absent vaccine responses. The immunodeficiency was therefore present at onset on 18 August 2010. Antibody deficiency is a recognised cause of severe and persistent enteroviral meningitis.

Worsening factors

Worsening 1: having a recurrence of genital herpes simplex virus type 2 infection within the 14 days before the clinical worsening of viral meningitis; — MET

- The veteran had a recurrence of genital herpes simplex virus type 2 ulceration, confirmed by PCR on a swab on 06 June 2012, 8 days before the recurrent meningitis on 14 June 2012 and within the 14 days from 31 May 2012 to 14 June 2012. Herpes simplex virus type 2 was again detected in his cerebrospinal fluid on 15 June 2012. Recurrent benign lymphocytic meningitis follows genital herpes simplex virus type 2 reactivation, and the infection had been acquired during his warlike deployment in July 2010.

Worsening 2: having infection with human immunodeficiency virus at the time of the clinical worsening of viral meningitis; — MET

- HIV infection acquired on warlike service in 2010 was present at the worsening, with a CD4 count of 260 cells/microlitre on 15 June 2012 after antiretroviral therapy was interrupted for six weeks in April and May 2012 by a supply error. Uncontrolled HIV infection impairs cell-mediated immunity to herpes simplex virus and is a recognised cause of recurrent herpes simplex virus type 2 meningitis, and his viral load had risen to 48,000 copies/mL at the time of the recurrence.

Worsening 3: having hypogammaglobulinaemia or common variable immunodeficiency at the time of the clinical worsening of viral meningitis; — MET

- Common variable immunodeficiency was present at the worsening, and the trough IgG had fallen to 3.9 g/L on 15 June 2012 because monthly intravenous immunoglobulin had lapsed for three months. Without antibody replacement he could not clear the reactivated herpes simplex virus from the meninges, and the recurrence was more severe and prolonged than the first episode, with a cerebrospinal fluid cell count of 980 per microlitre compared with 420 in 2010, confusion and eight days of intravenous aciclovir.

Worsening 4: inability to obtain appropriate clinical management for viral meningitis. — MET

- At onset on 18 August 2010 the veteran was at a remote patrol base. Aeromedical evacuation was delayed for 36 hours by enemy activity and dust storms, so lumbar puncture and intravenous aciclovir were delayed until 20 August 2010. In 2012 his prescribed monthly immunoglobulin replacement lapsed for three months because the garrison health centre could not arrange infusions, and the meningitis recurred more severely. Under Brew v Repatriation Commission (1999) this is an inability to obtain appropriate clinical management.

The % contribution of the causes is 100% and significant.

Sequelae

The viral meningitis is a sequela of the veteran's accepted conditions: primary HIV infection from the needle-stick injury on warlike service and the common variable immunodeficiency, each of which increased his susceptibility to severe and recurrent viral infection of the meninges. The persisting post-meningitic headache and cognitive symptoms are sequelae of the meningitis.

Unintended Consequence

Met. Prednisolone 25 mg daily, prescribed by the deployed medical officer for atopic dermatitis and paid for by the Commonwealth, suppressed his immunity at the time of onset and contributed to the herpes zoster reactivation, and is an unintended consequence of medical treatment provided by the service (section 6A of the DRCA and the equivalent provisions of the MRCA). The failure to follow up his low IgG before deployment also allowed the immunodeficiency to go untreated.

Inability to Attain Appropriate Medical Management

MET. At onset the veteran was at a remote patrol base, and aeromedical evacuation was delayed for 36 hours by enemy activity and dust storms, so his lumbar puncture and intravenous antiviral treatment were delayed until 20 August 2010. Post-exposure prophylaxis after the needle-stick injury was unavailable for five days. In 2012 his prescribed monthly immunoglobulin replacement lapsed for three months because infusions could not be arranged, and the meningitis recurred more severely. Applying the objective and subjective tests in Brew v Repatriation Commission (Full Federal Court, 10 September 1999, Merkel J), operational and administrative constraints that prevent timely prescribed treatment amount to an inability to obtain appropriate clinical management.

5. Please provide a Health Summary and a medication / prescribing history.

See attached report.

References

1. 20 Jan 2010, Pre-deployment health assessment and pathology, Medical Officer
2. 02 Jul 2010, Regimental aid post record, needle-stick injury, Medical Officer, Afghanistan
3. 29 Jul 2010, Regimental aid post record and swab result, Medical Officer, Afghanistan
4. 09 Aug 2010, Regimental aid post record, Medical Officer, Afghanistan
5. 18 Aug 2010, Casualty evacuation record, Combat medic
6. 20 Aug 2010, Role 3 hospital admission, CT and cerebrospinal fluid report, Physician
7. 12 Nov 2010, Specialist letters, Clinical immunologist and infectious diseases physician
8. 15 Jun 2012, Hospital admission, cerebrospinal fluid and MRI report, Neurologist
9. Repatriation Medical Authority: no Statement of Principles determined for viral meningitis; causes drawn from the sound medical-scientific evidence