Diagnostic dilemmas in acute intermittent porphyria. A case report

Acute Hepatic Porphyrias: "Purple Flags"-Clinical Features That Should Prompt Specific Diagnostic Testing

BACKGROUND

Porphyrias are a group of rare diseases leading to dysregulation in heme biosynthesis and the accumulation of heme precursors, including porphyrinogens, which in their oxidized states [porphyrins] are reddish or purple. Acute hepatic porphyrias (AHP) comprise four diseases that cause acute debilitating neurovisceral attacks. Despite diagnostic advances, AHP is often undiagnosed or misdiagnosed due to a lack of disease awareness, low clinical suspicion, variable presentation, and nonspecific symptoms that mimic more common diseases. Delays in diagnosis and treatment increase the risk of serious acute and chronic complications.

METHODS

In order to assess whether symptoms alone or in combination might be utilized as important indicators or "purple flags" that, when present, should alert clinicians to suspect AHP and pursue specific diagnostic testing, we conducted a comprehensive review of the literature on AHP, including cohort studies and case reports over two epochs, from 1980 to 2006 and from 2012 to 2018.

RESULTS

We found that severe abdominal pain, with or without acute central nervous system manifestations and peripheral neuropathy, continues to be the most frequent symptom. Hyponatremia, change in urine color, and certain chronic symptoms were also identified as features that should raise suspicion of AHP. To improve diagnosis of AHP, clinicians need to take a broad perspective, including demographic data and medical history, into consideration.

CONCLUSIONS

The clinical features of AHP continue to be severe pain, especially pain in the abdomen. Other features that should raise suspicion are autonomic, peripheral, or central neuropathies, hyponatremia, and red-purple urine color.

To be, or not to be… Guillain-Barré Syndrome

Guillain-Barré Syndrome (GBS) is currently the most frequent cause of acute flaccid paralysis on a global scale, being an autoimmune disorder wherein demyelination of the peripheral nerves occurs. Its main clinical features are a symmetrical ascending muscle weakness with reduced osteotendinous reflexes and variable sensory involvement. GBS most commonly occurs after an infection, especially viral (including COVID-19), but may also transpire after immunization with certain vaccines or in the development of specific malignancies. Immunoglobulins, plasmapheresis, and glucocorticoids represent the principal treatment modalities, however patients with severe disease progression may require supportive therapy in an intensive care unit. Due to its symptomology, which overlaps with numerous neurological and infectious illnesses, the diagnosis of GBS may often be misattributed to pathologies that are essentially different from this syndrome. Moreover, many of these require specific treatment methods distinct to those recommended for GBS, in lack of which the prognosis of the patient is drastically affected. Such diseases include exposure to toxins either environmental or foodborne, central nervous system infections, metabolic or serum ion alterations, demyelinating pathologies, or even conditions amenable to neurosurgical intervention. This extensive narrative review aims to systematically and comprehensively tackle the most notable and challenging differential diagnoses of GBS, emphasizing on the clinical discrepancies between the diseases, the appropriate paraclinical investigations, and suitable management indications.

Acute Neurological Manifestations of Porphyrias and its Types: A Systematic- Review

INTRODUCTION

Acute porphyrias cause life-threatening attacks of neurovisceral non-specific symptoms, so this condition mimics many acute medical and psychiatric diseases. The disease is very misdiagnosed, probably due to its low incidence and non-pathognomonic symptoms, this delays the effective treatment onset. Early diagnosis and treatment highly improve the prognosis and can prevent the development of neuropathic manifestations.

METHODS

We assembled a systematic review, following the PRISMA guidelines and using Pubmed as our database. Our aim was to show some peculiarities among patients that present neurological manifestations in acute porphyria attack. We obtained the patients' age, sex, clinical presentation, eurological manifestations and porphyria type of 16 patients. We also evaluated the time between symptoms onset and neurological manifestations. The average age was 28,4 ± 11,1; 50% of patients were male.

RESULTS

AIP was the most prevalent porphyria type. The average time between symptoms onset and neurological manifestations was of 9,53 ± 11,6 days. Abdominal pain; nausea and vomiting and psychiatric manifestations were the most common symptoms preceding neurological attacks. Seizures and consciousness disturbance were the most prevalent findings within an attack. We also presenting a case to illustrate how difficult this diagnosis can be.

Intensive care management of patients with acute intermittent porphyria: Clinical report of four cases and review of literature

Acute intermittent porphyria (AIP), the most common and the most severe form of acute hepatic porphyria, is an autosomal dominant condition. It results from lower-than-normal levels (less than 50%) of porphobilinogen (PBG) deaminase. Patients may present commonly with gastrointestinal complaints and neuropsychiatric manifestations. Diagnosis may be confirmed with the presence of intermediary metabolites of haem synthesis, amino levulinic acid (ALA) and PBG in urine or with specific enzyme assays. Abdominal pain is the most common symptom (90%). Peripheral polyneuropathy, primarily motor with flaccid paresis of proximal musculature, with or without autonomic involvement, is characteristic. Respiratory failure necessitates ventilator and intensive care support. Avoidance of precipitating factors and the use of haem preparations and intravenous dextrose form the basis of management. Gabapentin and propofol, rather than the conventional antiepileptics appear to be the appropriate choice for seizure control. Here, we present intensive care management of four cases of AIP with varying clinical presentation.

Acute intermittent porphyria with peripheral neuropathy complicated by small-fiber neuropathy

We describe a 60-year-old male patient with acute intermittent porphyria (AIP) who presented with initial abdominal pain and subsequent quadriplegia and respiratory failure. Small fiber neuropathy was demonstrated by measuring intra-epidermal nerve fiber density (IENFD) using protein gene product 9.5 (PGP 9.5) immunostaining on three consecutive skin punch biopsies of the distal lower limb. The biopsy findings demonstrated some correlation with progression of the patient's clinical condition. Neuropathy in AIP can have a small-fiber component rather than being solely a large-fiber neuropathy.

Biochemical compared to molecular diagnosis in acute intermittent porphyria

The biochemical and the molecular diagnoses of an inherited porphyria require experience. False positive or negative screening tests and the low penetrance of the disease make a correct diagnosis difficult.The biochemical and the molecular procedures for the diagnosis of acute intermittent porphyria were applied to five unrelated patients suffering from acute intermittent porphyria. All patients were shown to be gene carriers of acute intermittent porphyria by both methods. The two different possibilities of the diagnosis corresponded well. In a family definitively identified by molecular diagnosis of one of the patients and his relatives, the patient's two children were asymptomatic. His son was shown to be a gene carrier of the father's deficiency by biochemical as well as molecular analysis, whereas his daughter was not affected by acute intermittent porphyria.