The food base of many communities in the Amazon, whether rural or urban, is in regional fish. This is one reason that also explains the concentration of cases of the so-called "black urine disease", the Haff's Syndrome, a rare non-genetic, infectious disease, transmitted by the toxin ingested from some fish, even if cooked. Currently, there is still no closed list of species of the animal most likely to transmit the disease, with incidences varying in each location. The syndrome, identified in 1924, almost a century ago, in Europe, was first identified in Brazil in 2008, in the state of Amazonas, and since then, sporadic outbreaks of cases have been reported in the region.

The clinical picture is characterized by acute, generalized and intense pain and dark urine, as was the case of Everaldo Paz do Nascimento Santana, 38, resident of the community of Amapá, city of Belterra, located in the metropolitan region of Santarem, west of Pará. He had the symptoms of Haff's syndrome on September 17th this year, after eating fish of the pacu species. Everaldo was hospitalized and recovered without sequels, but he lost his brother, who, according to the death certificate, was a victim of the syndrome.

Everaldo says that three hours after eating the fish he started to feel pain in his neck. When I realized that this was not normal, I went to Belterra hospital. There I received several medications to lower my pressure and to try to relieve the pain, but nothing worked.

After being discharged from the hospital, still feeling some symptoms, Everaldo remembers that he didn't connect what happened to him to the fish consumption. For this reason, his brother consumed on Sunday morning a piece of the Pacu tail that was stored in the fridge.

"My brother wasn't home on Saturday when I ate the fish, he came home on Sunday and ate just a piece of the tail. Then my brother went to the hospital with symptoms that became worse very fast, besides the strong pain all over his body, he couldn't breathe anymore, he went straight to the oxygen balloon, they even gave him morphine, and the pain didn't go away", he recalled.

Edivaldo do Nascimento Melo, 52, Everaldo's brother, was hospitalized for eight days and died on September 25th. However, the symptoms presented by his brother were only related to Haff's syndrome on Monday (19), when the health surveillance was at Belterra's Hospital and talked to Everaldo about the high number of cases in the city.

"Until then, I didn't know that this was happening again in the city. Unfortunately, I learned about it from the health surveillance agent in Santarem. She told me about the increase of cases. If I had known about it, I would never have consumed the fish", he highlights.

Everaldo remembers that after his brother's urine turned black, he was transferred to the Municipal Hospital of Santarém and later to the Regional Hospital of Baixo Amazonas, where he died.

In Edivaldo's death certificate, there is a sequence of causes of death: Circulatory shock, upper digestive hemorrhage, disseminated intravascular coagulation, Haff's Syndrome.

Diagnosis increasing since 2021

In late 2021, there was a significant increase in diagnoses in the country, especially in the Amazon, with an outbreak of contagion, mainly through the ingestion of fish such as the Tambaqui species. According to the epidemiological bulletin of the Ministry of Health, of the 132 compatible cases that year, 106 were in the Amazon (77 in Amazonas, 25 in Pará, and 4 in Amapá).

This year, in the last semester, again an outbreak. Until November, 79 suspected cases of Haff's disease were reported in Pará, 13 of them in the municipality of Santarém, besides 110 compatible cases in Amazonas and 17 in Amapá.

Studies have not yet managed to identify the causes of the disease

According to the Health Surveillance Foundation of Amazonas Dr. Rosemary Costa Pinto, (FVS-RCP), the Black Urine disease is a syndrome still without a defined cause, characterized by a clinical condition that triggers the rhabdomyolysis picture (degradation of muscle tissue that releases a harmful protein in the blood) with sudden onset of stiffness, muscle pain and dark urine. The fish species most related to cases compatible with Haff's disease in Amazonas are pacu, tambaqui, and pirapitinga. The relationship between the species and the toxin that is transmitted is still being investigated.

"There is a working group investigating the disease composed of several state institutions, including the FVS-RCP.  There are still no conclusions about the studies for Haff's Disease in Brazil that highlight causes and prevention measures against the disease," the Foundation said in a statement.

While science is still searching for answers about the disease, the indications from the health area, at the moment, are that, as soon as the symptoms appear, the person should look for the nearest health unit and drink plenty of water until they receive treatment. One of the consequences of the syndrome is to lead to severe cases of dehydration and kidney failure, so it is important to be careful.

The Pará State Health Secretary, SESPA, also explains that there are no tests that confirm the disease, so the diagnosis is still made by excluding possibilities and by the symptoms presented by the patient.