Penile fracture is rupture of one or both of the tunica albuginea, the fibrous coverings that envelop the peniss corpora cavernosa. It is caused by rapid blunt force to an erect penis, usually during vaginal intercourse, or aggressive masturbation. It sometimes also involves partial or complete rupture of the urethra or injury to the dorsal nerves, veins and arteries. Signs and symptoms
A popping or cracking sound, significant pain, swelling, immediate loss of erection leading to flaccidity, and skin hematoma of various sizes are commonly associated with the sexual event. Causes
Penile fracture is a relatively uncommon clinical condition. Vaginal intercourse and aggressive masturbation are the most common causes. A 2014 study of accident and emergency records at three hospitals in Campinas, Brazil, showed that woman on top positions caused the greatest risk with the missionary position being the safest. The research conjectured that when the receptive partner is on top, they usually control the movement and are not able to interrupt movement when the penis suffers a misaligned penetration. Conversely, when the penetrative partner is controlling the movement, they have better chances of stopping in response to pain from misalignment, minimizing harm.The practice of taqaandan (also taghaandan) also puts men at risk of penile fracture. Taqaandan, which comes from a Kurdish word meaning "to click", involves bending the top part of the erect penis while holding the lower part of the shaft in place, until a click is heard and felt.
Nezelof syndrome is an autosomal recessive congenital immunodeficiency condition due to underdevelopment of the thymus. The defect is a type of purine nucleoside phosphorylase deficiency with inactive phosphorylase, this results in an accumulation of deoxy-GTP which inhibits ribonucleotide reductase. Ribonucleotide reductase catalyzes the formation of deoxyribonucleotides from ribonucleotides, thus, DNA replication is inhibited. Symptoms and signs
This condition causes severe infections. it is characterized by elevated immunoglobulins that function poorly. Other symptoms are:
Bronchiectasis
Hepatosplenomegaly
Pyoderma
Emphysema
Diarrhea

Cause
Genetically speaking, Nezelof syndrome is autosomal recessive. the condition is thought to be a variation of severe combined immunodeficiency (SCID). However, the precise cause of Nezelof syndrome remains uncertain

Mechanism
In the mechanism of this condition, one first finds that the normal function of the thymus has it being important in T-cell development and release into the bodys blood circulation Hassals corpuscles absence in thymus(atrophy) has an effect on T-cells. Diagnosis
The diagnosis of Nezelof syndrome will indicate a deficiency of T-cells, additionally in ascertaining the condition the following is done:
Blood test (B-cells will be normal)
X-ray of thymus (atrophy present)

Differential diagnosis
The differential diagnosis for this condition consists of acquired immune deficiency syndrome and severe combined immunodeficiency syndrome

Treatment
In terms of treatment for individuals with Nezelof syndrome, which was first  characterized in 1964, includes the following(how effective bone marrow transplant is uncertain) :

Antimicrobial therapy
IV immunoglobulin
Bone marrow transplantation
Thymus transplantation
Thymus factors

See also
List of radiographic findings associated with cutaneous conditions

References
Further reading
Lavini, Corrado; Moran, Cesar A.; Uliano, Morandi; Schoenhuber, Rudolf (2009-05-08). Thymus Gland Pathology: Clinical, Diagnostic and Therapeutic Features. Springer Science & Business Media. ISBN 9788847008281. External links
PubMed