Here are some weird dialysis complications:

AV access steal syndrome: painful ischemia of the hand secondary to the AV fistula or graft shunting blood away from the distal limb.

Hemodialysis-associated amyloidosis:
β2 microglobulin (B2M) is a normal protein in serum. It gets filtered in the kidneys but can't pass through the membranes of dialysis machines, therefore it accumulates and leads to amyloidosis. Most common presentation is carpal tunnel syndrome.

It's a chronic complication that appears after years of hemodialysis.

Dialysis disequilibrium syndrome:
Cerebral tissue takes longer to adjust to changes in osmolarity, so when you do hemodialysis (especially the first time) osmolarity will change too rapidly for cerebral tissue to adjust leading to cerebral edema.

Dialysis-associated aluminum toxicity:
Previously, we were using unfiltered water for dialysate fluid preparation which contained some amount of aluminum that normally gets filtered through the kidneys in healthy individuals, but accumulates in patients with renal failure leading to aluminum toxicity.

MHC & HLA

In humans, the Major HistoCompatibility (MHC) molecule is called the Human Leukocyte Antigen (HLA) system.

The MHC genes are codominantly expressed, which means that each individual expresses these genes from both the alleles on the cell surface. Furthermore, they are inherited as haplotypes, or one from each parent. This makes a person half identical to each of his or her parents with respect to the MHC complex. This also leads to a 25% chance that an individual might have a sibling who is HLA identical.

Human HLA genes code for 3 major class I alleles (HLA-A, -B, -C), and 3 major class II alleles (HLA-DR, -DQ, -DP). Polymorphisms in HLA, especially HLA-A, -B, and -DR loci, are important biological barriers to a successful transplantation, and may be part of many autoimmune diseases.

The MHC molecules are divided into 2 classes. The class I molecules are normally expressed on all nucleated cells, whereas the class II molecules are expressed only on the professional antigen-presenting cells (APCs), such as dendritic cells, activated macrophages, and B cells. The physiologic function of the MHC molecules is to present antigenic peptides to T cells. The class I molecules present antigenic peptides from within the cell (eg, self-antigens, intracellular viruses, tumor antigens) to CD8 T cells. The class II molecules present extracellular antigens such as extracellular bacteria to CD4 T cells.

Diabetes mellitus (DM) comes from the Greek roots 'diabetes' which means (pass through; a lot of urine) and the Latin word 'mellitus' meaning (honey-like, sweet), while the word insipidus in diabetes insipidus (DI) comes from Latin which basically means (tasteless).

This is because in times gone, when a patient urinated a lot, he was said to have diabetes. But to distinguish whether it was DM or DI, physicians had to taste the urine of the patient; if it was sweet, that is, mellitus, then it's DM. If it was tasteless, or insipidus, then it's DI.

It is possible for patients to be misdiagnosed with PCOS when in fact they have Cushing's syndrome, some form of congenital adrenal hyperplasia, or an androgen-secreting tumor as they all have a highly similar phenotype.

This is why the Rotterdam criteria explicity states that you can only make the diagnosis of PCOS after the exclusion of other etiologies.

Acute tubular necrosis (ATN)

• Damage to epithelial cells in kidney tubules.
• Leads to oliguria that is unresponsive to fluids, which becomes polyuria in the recovery phase.
• Muddy-brown casts on urinalysis.
• Causes:-
- Severe kidney ischemia
- Contrast agent
- Medications (aminoglycosides, amphotericin)
- Hemo-/myoglobinuria
- Uric acid

Acute interstitial nephritis (AIN)

• Type IV hypersensitivity reaction against the tubules & interstitium of the kidney.
• Polyuria.
• Sterile pyuria, WBC cast ± hematuria.
• possibly fever, rash, & eosinophiluria (rare, but eosinophilia is more common).

• Causes:
   - PPIs
- Antibiotics
- NSAIDs
- Loop diuretics
- Anticonvulsants

Papillary necrosis

• Renal papillary ischemia & necrosis.
• Sloughing of necrotic material may lead to ureteral obstruction
• Flank pain
• Hematuria, proteinuria, sterile pyuria
• Usually due to:-
   - DM
   - NSAIDs
   - Sicke cell anemia
   - Pyelonephritis
   - TB

.

أحسنت

نتعلم منك استاذي🍻

Calcium, PTH, vitamin D, and calcitonin

While some studies report a high correlation between loss of cremasteric reflex and testicular torsion, there are a surprising number of studies reporting the persistence of the reflex during verified cases of torsion. Additionally, other studies confirm that it is also absent from significant numbers of males and more so at younger ages. The frequency of the intact reflex has been reported in 61.7% to 100% of boys between 24 months and 12 years of age.